Latest Technology (A-Z)

DHCP-(Dynamic Host Control Protocol)

2010-02-13T01:01:00.002+05:30

IP addresses, by contrast, not only must be unique on a given internetwork, but
also must reflect the structure of the internetwork. As noted above, they contain a
network part and a host part, and the network part must be the same for all hosts
on the same network. Thus, it is not possible for the IP address to be configured once
into a host when it is manufactured, since that would imply that the manufacturer
knew which hosts were going to end up on which networks, and it would mean that
a host, once connected to one network, could never move to another. For this reason,
IP addresses need to be reconfigurable.

In addition to an IP address, there are some other pieces of information a host
needs to have before it can start sending packets. The most notable of these is the
address of a default router—the place to which it can send packets whose destination
address is not on the same network as the sending host.
Most host operating systems provide a way for a system administrator, or even
a user, to manually configure the IP information needed by a host. However, there
are some obvious drawbacks to such manual configuration. One is that it is simplya lot of work to configure all the hosts in a large network directly, especially when
you consider that such hosts are not reachable over a network until they are configured.

Even more importantly, the configuration process is very error-prone, since it is
necessary to ensure that every host gets the correct network number and that no two
hosts receive the same IP address. For these reasons, automated configuration methods
are required. The primary method uses a protocol known as the Dynamic Host
Configuration Protocol (DHCP).

DHCP relies on the existence of a DHCP server that is responsible for providing
configuration information to hosts. There is at least one DHCP server for an administrative
domain. At the simplest level, the DHCP server can function just as a centralized
repository for host configuration information. Consider, for example, the problem of
administering addresses in the internetwork of a large company. DHCP saves the network
administrators from having to walk around to every host in the company with a
list of addresses and network map in hand and configuring each host manually. Instead,
the configuration information for each host could be stored in the DHCP server and
automatically retrieved by each host when it is booted or connected to the network.
However, the administrator would still pick the address that each host is to receive;
he would just store that in the server. In this model, the configuration information for
each host is stored in a table that is indexed by some form of unique client identifier,
typically the “hardware address” (e.g., the Ethernet address of its network adaptor).
A more sophisticated use of DHCP saves the network admininstrator from even
having to assign addresses to individual hosts. In this model, the DHCP server maintains
a pool of available addresses that it hands out to hosts on demand. This considerably
reduces the amount of configuration an administrator must do, since now it is
only necessary to allocate a range of IP addresses (all with the same network number)
to each network.

Since the goal of DHCP is to minimize the amount of manual configuration
required for a host to function, it would rather defeat the purpose if each host had
to be configured with the address of a DHCP server. Thus, the first problem faced by
DHCP is that of server discovery.

To contact a DHCP server, a newly booted or attached host sends a
DHCPDISCOVER message to a special IP address (255.255.255.255) that is an IP broadcast
address. This means it will be received by all hosts and routers on that network.
(Routers do not forward such packets onto other networks, preventing broadcast to
the entire Internet.) In the simplest case, one of these nodes is the DHCP server for the
network. The server would then reply to the host that generated the discovery message
(all the other nodes would ignore it). However, it is not really desirable to require one
DHCP server on every network because this still creates a potentially large number
of servers that need to be correctly and consistently configured. Thus, DHCP uses theconcept of a relay agent. There is at least one relay agent on each network, and it isconfigured with just one piece of information: the IP address of the DHCP server. Whena relay agent receives a DHCPDISCOVER message, it unicasts it to the DHCP server and awaits the response, which it will then send back to the requesting client. The processof relaying a message from a host to a remote DHCP server is shown in diagram 1-A Diagram 1-B shows the format of a DHCP message. The message is actually sent using a protocol called UDP (the User Datagram Protocol) that runs over IP.
DHCP is derived from an earlier protocol called BOOTP, and some of the packet
fields are thus not strictly relevant to host configuration. When trying to obtain configuration information, the client puts its hardware address (e.g., its Ethernet address) inthe chaddr field. The DHCP server replies by filling in the yiaddr (“your” IP address)field and sending it to the client. Other information such as the default router to be used by this client can be included in the options field.
In the case where DHCP dynamically assigns IP addresses to hosts, it is clear
that hosts cannot keep addresses indefinitely, as this would eventually cause the server to exhaust its address pool. At the same time, a host cannot be depended upon to give back its address, since it might have crashed, been unplugged from the network,or been turned off. Thus, DHCP allows addresses to be “leased” for some period of time. Once the lease expires, the server is free to return that address to its pool. A host with a leased address clearly needs to renew the lease periodically if in fact it is still connected to the network and functioning correctly.
It is important to note that DHCP may also introduce some more complexity into network management,since it makes the binding between physical hosts and IP addresses muchmore dynamic. This may make the network manager’s job more difficult if, for example,it becomes necessary to locate a malfunctioning host.

BLU-RAY TECHNOLOGY

2009-12-13T09:00:00.001+05:30

DEFINITION OF BLU-RAY:

Blu-ray, also known as Blu-ray Disc (BD), is the name of a next-generation optical disc format jointly developed by the Blu-ray Disc Association (BDA), a group of the world's leading consumer electronics, personal computer and media manufacturers (including Apple, Dell, Hitachi, HP, JVC, LG, Mitsubishi, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony, TDK and Thomson). The format was developed to enable recording, rewriting and playback of high-definition video (HD), as well as storing large amounts of data. The format offers more than five times the storage capacity of traditional DVDs and can hold up to 25GB on a single-layer disc and 50GB on a dual-layer disc. This extra capacity combined with the use of advanced video and audio codecs will offer consumers an unprecedented HD experience.

DEVELOPERS OF BLU-RAY:
The Blu-ray Disc format was developed by the Blu-ray Disc Association (BDA), a group of leading consumer electronics, personal computer and media manufacturers, with more than 180 member companies from all over the world. The Board of Directors currently consists of:

Apple Computer, Inc.
Dell Inc.
Hewlett Packard Company
Hitachi, Ltd.
LG Electronics Inc.
Matsushita Electric Industrial Co., Ltd.
Mitsubishi Electric Corporation
Pioneer Corporation
Royal Philips Electronics
Samsung Electronics Co., Ltd.
Sharp Corporation
Sony Corporation
Sun Microsystems, Inc.
TDK Corporation
Thomson Multimedia
Twentieth Century Fox
Walt Disney Pictures
Warner Bros. Entertainment.

DATA STORAGE CAPACITY IN BLU-RAY DISC:
A single-layer disc can hold 25GB.
A dual-layer disc can hold 50GB.

To ensure that the Blu-ray Disc format is easily extendable (future-proof) it also includes support for multi-layer discs, which should allow the storage capacity to be increased to 100GB-200GB (25GB per layer) in the future simply by adding more layers to the discs.

WORK FUNCTION OF BLU-RAY:
According to the Blu-ray Disc specification, 1x speed is defined as 36Mbps. However, as BD-ROM movies will require a 54Mbps data transfer rate the minimum speed we're expecting to see is 2x (72Mbps). Blu-ray also has the potential for much higher speeds, as a result of the larger numerical aperture (NA) adopted by Blu-ray Disc. The large NA value effectively means that Blu-ray will require less recording power and lower disc rotation speed than DVD and HD-DVD to achieve the same data transfer rate. While the media itself limited the recording speed in the past, the only limiting factor for Blu-ray is the capacity of the hardware. If we assume a maximum disc rotation speed of 10,000 RPM, then 12x at the outer diameter should be possible (about 400Mbps). This is why the Blu-ray Disc Association (BDA) already has plans to raise the speed to 8x (288Mbps) or more in the future.

While current optical disc technologies such as DVD, DVD±R, DVD±RW, and DVD-RAM rely on a red laser to read and write data, the new format uses a blue-violet laser instead, hence the name Blu-ray. Despite the different type of lasers used, Blu-ray products can easily be made backwards compatible with CDs and DVDs through the use of a BD/DVD/CD compatible optical pickup unit. The benefit of using a blue-violet laser (405nm) is that it has a shorter wavelength than a red laser (650nm), which makes it possible to focus the laser spot with even greater precision. This allows data to be packed more tightly and stored in less space, so it's possible to fit more data on the disc even though it's the same size as a CD/DVD. This together with the change of numerical aperture to 0.85 is what enables Blu-ray Discs to hold 25GB/50GB. Recent development by Pioneer has pushed the storage capacity to 500GB on a single disc by using 20 layers.

2012

2009-12-13T08:59:00.000+05:30

2012 END OF THE WORLD - BELIEFS

SCIENTIFIC EXPERTS from around the world are predicting that five years from now, all life on Earth could well come to an end. Some are saying it’ll be humans that would set it off. Others believe that a natural phenomenon will be the cause. And the religious folks are saying it’ll be God himself who would press the stop button. The following are some likely arguments as to why the world would end by the year 2012.

Reason one: Mayan calendar

The first to predict 2012 as the end of the world were the Mayans, a bloodthirsty race that were good at two things -- building highly accurate astrological equipment out of stone and sacrificing virgins.

Thousands of years ago they managed to calculate the length of the lunar moon as 329.53020 days, only 34 seconds out. The Mayan calendar predicts that the earth will end on December 21, 2012. Given that they were pretty close to the mark with the lunar cycle, it’s likely they’ve got the end of the world right as well.

Reason two: Sun storms

Solar experts from around the world monitoring the sun have made a startling discovery. Our sun is in a bit of strife. The energy output of the sun is, like most things in nature, cyclic and it’s supposed to be in the middle of a period of relative stability. However, recent solar storms have been bombarding the earth with lot of radiation energy. It’s been knocking out power grids and destroying satellites. This activity is predicted to get worse and calculations suggest it’ll reach its deadly peak sometime in 2012.

Reason three: The atom smasher

Scientists in Europe have been building the world’s largest particle accelerator. Basically, its a 27 km tunnel designed to smash atoms together to find out what makes the universe tick. However, the mega-gadget has caused serious concern, with some scientists suggesting that it’s properly even a bad idea to turn it on in the first place. They’re predicting all manner of deadly results, including mini black holes. So when this machine is fired up for its first serious experiment in 2012, the world could be crushed into a super-dense blob the size of a basketball.

Reason four: The Bible says it

If having scientists warning us about the end of the world isn’t bad enough, religious folks are getting in on the act as well. Interpretations of the Christian Bible reveal that the date for Armageddon, the final battle between good an evil, has been set for 2012. The I Ching, also known as the Chinese Book of Changes, says the same thing, as do various sections of the Hindu teachings.

Reason five: Super volcano

Yellowstone National Park in United States is famous for its thermal springs and old faithful geyser. The reason for this is simple -- it’s sitting on top of the world’s biggest volcano and geological experts are beginning to get nervous sweats. The Yellowstone volcano has a pattern of erupting every 650,000 years or so, and we’re many years overdue for an explosion that will fill the atmosphere with ash, blocking the sun and plunging the earth into a frozen winter that could last up to 15,000 years. The pressure under the Yellowstone is building steadily, and geologists have set 2012 as a likely date for the big bang.

Reason six: The physicists

This one’s case of bog -- simple maths mathematics. Physicists at Berkely University have been crunching the numbers. They’ve determined that the earth is well overdue for a major catastrophic event. Even worse, they’re claiming that their calculations prove that we’re all going to die, very soon. They are also saying that their prediction comes with a certainty of 99 per cent; and 2012 just happens to be the best guess as to when it occurs.

Reason seven: Earth’s magnetic field

We all know the Earth is surrounded by a magnetic field that shields us from most of the sun’s radiation. What you might not know is that the magnetic poles we call North and South have a nasty habit of swapping places every 750,000 years or so -- and right now we’re about 30,000 years overdue. Scientists have noted that the poles are drifting apart roughly 20-30 kms each year, much faster than ever before, which points to a pole-shift being right around the corner. While the pole shift is under way, the magnetic field is disrupted and will eventually disappear, sometimes for up to 100 years. The result is enough UV outdoors to crisp your skin in seconds, killing everything it touches

Microsoft Surface

2009-11-04T07:55:00.005+05:30

Microsoft Surface Introduction:

After establishing the lead in software industry, Microsoft toyed with various hardware. We saw xBox, Zune etc. Then a bigger project was under development under code name Milan, which was all about Microsoft Surface. Milan was aimed to leverage the perfect combination of hardware and software. Manipulating digital content using hand gestures, motions and physical objects is all about Microsoft Surface.

The 30-inch screen brings on all the excitement about Microsoft Surface. This 22 inches high, 21 inches deep, 42 inches wide innovative product costs as much as US$ 10000 and it takes some time to be affordable to all. Probably in another 4-5 years, the surface becomes so common that, every house and business will have a Surface and think about Microsoft Surface as part of their furniture, which is intelligent.

Many had a wrong impression about Microsoft Surface. They thought it is another glorified and hyped touch screen computer. And they are proved wrong by the features provided in the Microsoft surface. The touch screen computers enable users to do away with keyboard and mouse.

They can navigate the menu by touching various options to reach a logical end of viewing data or printing. And there ends the comparison. Microsoft Surface can do many more things, which you think are not possible!

The number of fingers detected by the multitouch sensor is limited only by the individual software designer’s desire – the hardware itself supports as many simultaneous prods as you can throw at it.

Microsoft CEO Steve Ballmer unveiled Microsoft Surface on May 29, 2007 and the whole world came to know about Microsoft Surface. Microsoft has some partners like Star wood Hotels & Resorts Worldwide, International Game Technology , Harrah's Entertainment, T-Mobile etc readily willing to experiment Microsoft Surface in real world situation in their business.

Microsoft Surface Features:

Direct interaction: Facility to manage digital information with hand gestures and touch instead on mouse and keyboard.

Main interface components: Direct interaction, multi-touch contact, a multi-user experience, and object recognition.

Multi-touch contact: User need not use only one finger to manage digital data. If user dips five fingers in five different colors in the on screen paint palette and draws five lines with five fingers, you get five lines with five colors.

Multi-user experience: Typical computers accept only one keyboard and a mouse. Microsoft Surface accepts multiple inputs from multiple users. More than one person sitting across the Surface, can do independent work on the same Surface.

Orientation: Horizontal – like a table to allow users to use, share and create experiences together.
CPU: Core 2 Duo processor

Processor: 1 GHz processor.

Installed Memory: 2GB of RAM

Hard drive: Yes

Object recognition: The system can identify physical objects placed on the Surface. It can relate the appropriate software for the appropriate item placed on surface. Objects may be recognized based on their shape or on special codes affixed to them.

Display Type: 30-inch Flat panel display

Graphics Card: 256MB graphics card.

Projector: DLP light engine like the one used in rear-projection HDTV.

Cameras: Five cameras with infrared filters - net resolution of 1280 x 960

Material: The tabletop is acrylic, and its interior frame is powder-coated steel.

Surface: Not touch-sensitive surface. When you place or drag a finger, internal projector lights screen from beneath.

Power Supply: Standard American 110–120V power

Operating System: The custom software platform runing on Windows Vista

Network Connectivity: Wired Ethernet 10/100 and wireless 802.11 b/g and Bluetooth 2.0 connectivity.

Dimensions: 22 inches high, 21 inches deep and 42 inches wide.

Weight: 150 pounds

Ideal for: Restaurants, games, shops and Entertainment

Microsoft Surface Approximative Price: US$ 10000

Other features:

Drag & Drop: Like any widows Operating system, all items can be dragged and dropped.

Automatic Identification: Can identify objects. Place your Digital camera on the surface and you can see the photos displayed on the surface without actually downloading!
Initial customers: Harrah's Entertainment, Starwood Hotels and Resorts, T-Mobile and IGT.

Nano Technology

2009-11-04T07:41:00.002+05:30

Introduction to Nanotechnology

Nanotechnology is defined as the study and use of structures between 1 nanometer and 100 nanometers in size. To give you an idea about this is, it would take eight 100 nanometer particles side by side to match the width of a human hair.
Introduction to the Nanoparticles
Scientists have been studying and working with nano particles for centuries, but the effectiveness of their work has been hampered by their inability to see the structure of nano particles. In recent decades the development of microscopes capable of displaying particles as small as atoms has allowed scientists to see what they are working with.

Applications of nanotechnology:

Medicine
Researchers are developing customized nano particles the size of molecules that can be deliver drugs directly to diseased cells in human body. When it's perfected, this method should be greatly reduce the damage treatment such as chemotherapy does to a patient's healthy cells
Nano medicine refers to future developments in medicine that will be based on the ability to build nano robots. In the future these nano robots could actually be programmed to repair specific diseased cells, functioning in a similiar way to antibodies in our natural healing processes

Electronics
Nanotechnology holds some answers for how we might increase the capabilities of electronics devices while we reduce their weight and power consumption.

Space
Nanotechnology may hold the key to making space-flight more practical. Advancements in nano materials make lightweight solar sails and a cable for the space elevator possible. By significantly reducing the amount of rocket fuel required, these advances could lower the cost of reaching orbit and traveling in space.

Food
Nanotechnology is having an impact on several aspects of food science, from how food is grown to how it is packaged. Companies are developing nano materials that will make a difference not only in the taste of food, but also in food safety, and the health benefits that food delivers

Fuel Cells
Nanotechnology is being used to reduce the cost of catalysts used in fuel cells to produce hydrogen ions from fuel such as methanol and to improve the efficiency of membranes used in fuel cells to separate hydrogen ions from other gases such as oxygen.

Solar Cells
Companies have developed nanotech solar cells that can be manufactured at significantly lower cost than conventional solar cells.

Batteries
Companies are currently developing batteries using nano materials. One such battery will be a good as new after sitting on the shelf for decades. Another battery can be recharged significantly faster than conventional batteries.

Fuels
Nanotechnology can address the shortage of fossil fuels such as diesel and gasoline by making the production of fuels from low grade raw materials economical, increasing the mileage of engines, and making the production of fuels from normal raw materials more efficient.

Chemical Sensors
Nanotechnology can enable sensors to detect very small amounts of chemical vapors. Various types of detecting elements, such as carbon nano tubes, zinc oxide nanowires or palladium nano particles can be used in nanotechnology-based sensors. Because of the small size of nano tubes, nano wires, or nano particles, a few gas molecules are sufficient to change the electrical properties of the sensing elements. This allows the detection of a very low concentration of chemical vapors.

Better Air Quality
Nanotechnology can improve the performance of catalysts used to transform vapors escaping from cars or industrial plants into harmless gasses. That's because catalysts made from nano particles have a greater surface area to interact with the reacting chemicals than catalysts made from larger particles. The larger surface area allows more chemicals to interact with the catalyst simultaneously, which makes the catalyst more effective.

Cleaner Water
Nanotechnology is being used to develop solutions to three very different problems in water quality. One challenge is the removal of industrial wastes, such as a cleaning solvent called TCE, from groundwater. Nano particles can be used to convert the contaminating chemical through a chemical reaction to make it harmless. Studies have shown that this method can be used successfully to reach contaminates dispersed in underground ponds and at much lower cost than methods which require pumping the water out of the ground for treatment.

Fabric
Making composite fabric with nano-sized particles or fibers allows improvement of fabric properties without a significant increase in weight, thickness, or stiffness as might have been the case with previously-used techniques.

Sporting Goods
If you are a tennis or golf fan, you will be glad to hear that even sporting goods has wandered into the nano realm. Current nanotechnology applications in the sports arena include increasing the strength of tennis racquets, filling any imperfections in club shaft materials and reducing the rate at which air leaks from tennis balls.

Multiple Access Techniques In Cellular Systems

2009-10-12T23:06:00.002+05:30

hi this is an article about the multiple access techniques used in the cellular systems.

The goal in the design of a cellular system is to be able to handle as many calls as possible in a given bandwidth with the specifi ed blocking probability (reliability).

Multiplexing deals with the division of the resources to create multiple channels.
Multiplexing can create channels in frequency, time, etc., and the corresponding
terms are then frequency division multiplexing (FDM), time division
multiplexing (TDM), etc. Since the amount of spectrum available is limited,
we need to fi nd ways to allow multiple users to share the available spectrum
simultaneously. Shared access is used to implement a multiple access scheme when
access by many users to a channel is required.
For example, one cancreate multiple channels using TDM, but each of these channels can be accessedby a group of users using the ALOHA multiple access scheme. The multiple access schemes can be either reservation-based or random.
Multiple access schemes allow many users to share the radio spectrum.
Sharing the bandwidth effi ciently among users is one of the main objectives of
multiple access schemes .
The variability of wireless channels presentsboth challenges and opportunities in designing multiple access communicationssystems. Multiple access strategy has an impact on robustness and interference levels generated in other cells. Therefore, multiple access schemes are designed to maintain orthogonality and reduce interference effects.

Multiple access schemes can be classifi ed as reservation-based multiple
access (e.g., FDMA, TDMA, CDMA) and random multiple access (e.g.,
ALOHA, CSMA) . If data traffi c is continuous and a small
transmission delay is required (for example in voice communication) reservationbased
multiple access is used. The family of reservation-based multiple access
includes frequency division multiple access (FDMA), time division multiple access
(TDMA), and code division multiple access (CDMA). In many
wireless systems for voice communication, the control channel is based on random
multiple access and the communication channel is based on FDMA, TDMA, or
CDMA.
The reservation-based multiple access technique has a disadvantage in
that once the channel is assigned, it remains idle if the user has nothing to transmitwhile other users may have data waiting to be transmitted. This problem is critical when data generation is random and has a high peak-rate to average-rate ratio.
In this situation, random multiple access is more effi cient, because a communication
channel is shared by many users and users transmit their data in a random or
partially coordinated fashion.

ALOHA and carrier sense multiple access (CSMA)
are examples of random multiple access. If the data arrives in a random manner,
and the data length is large, then random multiple access combined with
a reservation protocol will perform better than both random- and reservationbased
schemes.

LAPTOPS

2009-10-12T20:50:00.003+05:30

hi in this article i posted about the the best ecnomical and worthful laptop dont wonder that is dell inspiron 15 models. it is one of the best laptops i never seen.

Specifications:

Processors : Intel® CoreTM 2 Duo Processor T6600 (2.20GHz/ 800 FSB/ 2MB Cache)

Operating System : Genuine Windows Vista® Home Basic (SP1) 32-Bit
Genuine Windows Vista® Home Premium (SP1) 32-Bit

Virtual Memory : Up to 4GB Dual Channel 800MHz DDR2 SDRAM.

Chipset : Intel® Cantiga GM45 Chipset

Graphics Card : Intel® Integrated Graphics Media Accelerator 4500MHD

LCD Display : Glossy 15.6" Widescreen XGA (1366x768)

Audio and Speakers : Intel High Definition Audio 2.0

Hard Drives : Up to 320GB configured with a 5400 RPM SATA hard drive

Optical Drives : DVD+/-RW with Dual Layer DVD+R write capability
Blu-Ray/CD/DVD Combo Drive

Power : Up to 9-cell Primary Battery

Camera : Built-in 1.3MP webcam

Wireless : Dell Wireless 1397 802.11g Mini-Card
(or)
Dell Wireless 1515 Wireless-N Mini-Card

I/O Ports : VGA, RJ11 (via optional USB dongle),
RJ45,Audio jacks (1 line-in, 1-line out, 1 Mic-in),
1 Express Card 54mm slot, 3 mini-card slots,
2 USB 2.0 ports, Sim socket

GPRS in GSM

2009-10-02T09:16:00.003+05:30

hi this about the GPRS technology that is widely used in gsm phones.

The general packet radio service (GPRS) enhances GSM data services
signifi cantly by providing end-to-end packet switched data connections. This is
particularly effi cient in Internet/intranet traffi c, where short bursts of intense data
communications are actively interspersed with relatively long periods of inactivity.
Because there is no real end-to-end connection to be established, setting up a
GPRS call is almost instantaneous and users can be continuously on-line. Users
have the additional benefi ts of paying for the actual data transmitted, rather than
for connection time. Because GPRS does not require any dedicated end-to-end
connection, it only uses network resources and bandwidth when data is actually
being transmitted. This means that a given amount of radio bandwidth can be
shared effi ciently among many users simultaneously.

The next phase in the high-speed road map is the evolution of current short
message service (SMS), such as smart messaging and unstructured supplementary
service data (USSD), toward the new GPRS, a packet data service using TCP/IP
and X.25 to offer speeds up to 115 kbps. GPRS has been standardized to optimally
support a wide range of applications ranging from very frequent transmissions
of medium to large data volume. Services of GPRS have been developed to
reduce connection set-up time and allow an optimum usage of radio resources.
GPRS provides a packet data service for GSM where time slots on the air interface
can be assigned to GPRS over which packet data from several mobile stations is
multiplexed.

A similar evolution strategy, also adopting GPRS, has been developed for
DAMPS (IS-136). For operators planning to offer wideband multimedia services,
the move to GPRS packet-based data bearer service is signifi cant; it is a relatively
small step compared to building a totally new 3G IMT-2000 network. Use of the
GPRS network architecture for IS-136 packet data service enables data subscription
roaming with GSM networks around the globe that support GPRS and
its evolution. The IS-136 packet data service standard is known as GPRS-136.
GPRS-136 provides the same capabilities as GSM GPRS. The user can access
either X.25 or an IP-based data network.

GPRS provides a core network platform for current GSM operators not
only to expand the wireless data market in preparation for the introduction of
3G services, but also a platform on which to build IMT-2000 frequencies should
they acquire them.

The implementation of GPRS has a limited impact on the GSM core network.
It simply requires the addition of new packet data switching and gateway
nodes, and an upgrade to existing nodes to provide a routing path for packet
data between the wireless terminal and a gateway node. The gateway node provides
interworking with external packet data networks for access to the Internet,
intranet, and databases.

GPRS supports all widely used data communicationsprotocols, including IP, so it is possible to
connect with any data source fromanywhere in the world using a GPRS mobile terminal.
GPRS supports applications ranging from low-speed short messages to high-speed corporate LAN communications.
However, one of the key benefi ts of GPRS — that it is connected through the
existing GSM air interface modulation scheme — is also a limitation, restricting its
potential for delivering higher data rates than 115 kbps. To build even higher rate
data capabilities into GSM, a new modulation scheme is needed.

GPRS can be implemented in the existing GSM systems. Changes are required
in an existing GSM network to introduce GPRS. The base station subsystem (BSS)
consists of a base station controller (BSC) and packet control unit (PCU). The
PCU supports all GPRS protocols for communication over the air interface. Its
function is to set up, supervise, and disconnect packet switched calls. The packet
control unit supports cell change, radio resource confi guration, and channel
assignment. The base station transceiver (BTS) is a relay station without protocol
functions. It performs modulation and demodulation.

write ur comments

HSCSD(High Speed Circuit Switching Data)

2009-10-02T09:09:00.003+05:30

hi this is one data transfering technology used in the GSM mobiles for internet usage.

High-speed circuit switched data (HSCSD) is a feature that enables the
co-allocation of multiple full rate traffi c channels (TCH/F) of GSM into an HSCSD
confi guration. The aim of HSCSD is to provide a mixture of services with different
air interface user rates by a single physical layer structure. The available capacity
of an HSCSD confi guration is several times the capacity of a TCH/F, leading to a
significant enhancement in air interface data transfer capability.

Ushering faster data rates into the mainstream is the new speed of
14.4 kbps per time slot and HSCSD protocols that approach wireline access
rates of up to 57.6 kbps by using multiple 14.4 kbps time slots. The increase
from the current baseline of 9.6 kbps to 14.4 kbps is due to a nominal reduction
in the error-correction overhead of the GSM radio link protocol (RLP),
allowing the use of a higher data rate.

For operators, migration to HSCSD brings data into the mainstream, enabled
in many cases by relatively standard software upgrades to base station (BS) and
mobile switching center (MSC) equipment. Flexible air interface resource allocation
allows the network to dynamically assign resources related to the air interface
usage according to the network operator’s strategy, and the end-user’s request
for a change in the air interface resource allocation based on data transfer needs.
The provision of the asymmetric air interface connection allows simple mobile
equipment to receive data at higher rates than otherwise would be possible with
a symmetric connection.

For end-users, HSCSD enables the roll-out of mainstream high-end segment
services that enable faster web browsing, fi le downloads, mobile video-conference
and navigation, vertical applications, telematics, and bandwidth-secure mobile
local area network (LAN) access. Value-added service providers will also be able
to offer guaranteed quality of service and cost-effi cient mass-market applications,
such as direct IP where users make circuit-switched data calls straight into a GSM
network router connected to the Internet. To the end-user, the value-added service
provider or the operator is equivalent to an Internet service provider that offers a
fast, secure dial-up Internet protocol service at cheaper mobile-to-mobile rates.
HSCSD is provided within the existing mobility management.
Roaming is also possible. The throughput for an HSCSD connection remains constant for the
duration of the call, except for interruption of transmission during handoff. The
handoff is simultaneous for all time slots making up an HSCSD connection. Endusers
wanting to use HSCSD have to subscribe to general bearer services. Supplementary
services applicable to general bearer services can be used simultaneously
with HSCSD.

Firmware on most current GSM PC cards needs to be upgraded. The reduced
RLP layer also means that a stronger signal strength is necessary. Multiple time
slot usage is probably only effi ciently available in off-peak times, increasing overall
off-peak idle capacity usage. HSCSD is not a very feasible solution for bursty
data applications.

please write ur comments.

Data Evolution in GSM Technology

2009-10-02T09:06:00.002+05:30

hi this is about the evolution in gsm technology for data transfers.

From a radio access perspective, adding 3G capabilities to 2G systems mainly
means supporting higher data rates. Possible scenarios depend on spectrum availability
for the network service provider. Depending on the spectrum situation,
two different migration paths can be supported:
Reframing of existing spectrum bands
New or modified spectrum bands
Two 3G radio access schemes are identifi ed to support the different spectrum
scenarios:
1. Enhanced data rates for GSM evolution (EDGE) with high-level modulation in
a 200 kHz TDMA channel is based on plug-in transceiver equipment, thereby
allowing the migration of existing bands in small spectrum segments.

2. Universal mobile telecommunications services (UMTS) is a new radio
access network based on 5 MHz WCDMA and optimized for effi cient support
of 3G services. UMTS can be used in both new and existing spectra.

From a network point of view, 3G capabilities implies the addition of packet
switched (PS) services, Internet access, and IP connectivity. With this approach,
the existing mobile networks reuse the elements of mobility support, user authentication/
service handling, and circuit switched (CS) services. With packet switched
services, IP connectivity can then be added to provide a mobile multimedia core
network by evolving the existing mobile network.

GSM is moving to develop enhanced cutting-edge, customer-focused solutions
to meet the challenges of the new millennium and 3G mobile services [29].
When GSM was fi rst introduced, no one could have predicted the dramatic growth
of the Internet and the rising demand for multimedia services. These developments
have brought about new challenges to the world of GSM. For GSM operators, the
emphasis is now rapidly changing from that of instigating and driving the development
of technology to fundamentally enabling mobile data transmission to that
of improving speed, quality, simplicity, coverage, and reliability in terms of tools
and services that will boost mass market take-up.

Users are increasingly looking to gain access to information and services
wherever they are and whenever they want. GSM should provide that connectivity.
Internet access, web browsing and the whole range of mobile multimedia capability
are the major drivers for development of higher data speed technologies.
Current data traffi c on most GSM networks is modest, less than 5% of total
GSM traffi c. But with the new initiatives coming to fruition during the course of
the next two to three years, exponential growth in data traffi c is forecast. The
use of messaging-based applications may reach up to about 90% by the year
2008. GSM data transmission using high-speed circuit switched data (HSCSD)
and GPRS may reach a penetration of about 80% by 2008 [1].
GSM operators have two nonexclusive options for evolving their networks
to 3G wideband multimedia operation: (1) using GPRS and EDGE in the existing
radio spectrum, and in small amounts of the new spectrum; or (2) using
WCDMA in the new 2 GHz bands, or in large amounts of the existing spectrum.
Both approaches offer a high degree of investment fl exibility because roll-out can
proceed in line with market demand with the extensive reuse of existing network
equipment and radio sites.

In the new 2 GHz bands, 3G capabilities are delivered using a new wideband
radio interface that offers much higher user data rates than are available
today — 384 kbps in the wide area and up to 2 Mbps in the local area. Of equal
importance for such services is the high-speed packet switching provided by GPRS
and its connection to public and private IP networks.

GSM and digital (D)AMPS (IS-136) operators can use existing radio bands
to deliver some of the 3G services, even without the new wideband spectrum
by evolving current networks and deploying GPRS and EDGE technologies.
In the early years of 3G service deployment, a large proportion of wireless traffi c
will still be voice-only and low-rate data. So whatever the ultimate capabilities
of 3G networks, effi cient and profi table ways of delivering more basic wireless
services are still needed.

The signifi cance of EDGE for today’s GSM operators is that it increases data
rates up to 384 kbps and potentially even higher in a good quality radio environment
using current GSM spectrum and carrier structures more effi ciently. EDGE
is both a complement and an alternative to new WCDMA coverage. EDGE also
has the effect of unifying the GSM, D-AMPS and WCDMA services through the
use of dual-mode terminals.

please write ur comments

Cellular Systems

2009-10-02T08:53:00.002+05:30

hi this is about the emerging cellular concepts and their origin. we are all using the cellular phones so we have to know about the fundamental concept implemented.

Most commercial radio and television systems are designed to cover as much
area as possible. These systems typically operate at maximum power and with
the tallest antennas allowed by the Federal Communications Commission (FCC).
The frequency used by the transmitter cannot be reused again until there is
enough geographical separation so that one station does not interfere signifi -
cantly with another station assigned to that frequency. There may even be a large
region between two transmitters using the same frequency where neither signal is
received.
The cellular system takes the opposite approach . It seeks to
make an effi cient use of available channels by employing low-power transmitters
to allow frequency reuse at much smaller distances . Maximizing
the number of times each channel may be reused in a given geographic area is the
key to an effi cient cellular system design.
Cellular systems are designed to operate with groups of low-power radios
spread out over the geographical service area. Each group of radios serve mobile
stations located near them. The area served by each group of radios is called a cell.
Each cell has an appropriate number of low-power radios to communicate within
the cell itself. The power transmitted by the cell is chosen to be large enough to
communicate with mobile stations located near the edge of the cell. The radius of
each cell may be chosen to be perhaps 28 km (about 16 miles) in a start-up system
with relatively few subscribers, down to less than 2 km (about 1 mile) for a mature
system requiring considerable frequency reuse.

As the traffi c grows, new cells and channels are added to the system. If an
irregular cell pattern is selected, it would lead to an ineffi cient use of the spectrum
due to its inability to reuse frequencies because of cochannel interference. In addition,
it would also result in an uneconomical deployment of equipment, requiring
relocation from one cell site to another. Therefore, a great deal of engineering
effort would be required to readjust the transmission, switching, and control
resources every time the system goes through its development phase. The use of a
regular cell pattern in a cellular system design eliminates all these diffi culties.
In reality, cell coverage is an irregularly shaped circle.
The exact coverage of the cell depends on the terrain and many other factors. For design purposes and as
a fi rst-order approximation, we assume that the coverage areas are regular polygons.
For example, for omnidirectional antennas with constant signal power, each
cell site coverage area would be circular. To achieve full coverage without dead
spots, a series of regular polygons are required for cell sites. Any regular polygon
such as an equilateral triangle, a square, or a hexagon can be used for cell design.
The hexagon is used for two reasons: a hexagonal layout requires fewer cells and,
therefore, fewer transmitter sites, and a hexagonal cell layout is less expensivecompared to square and triangular cells. In practice, after the polygons are drawn
on a map of the coverage area, radial lines are drawn and the signal-to-noise ratio
(SNR) calculated for various directions using the propagation models , or using appropriate computer programs . we assume regular polygons for coverage areas even though in
practice that is only an approximation.

please write ur comments about this post.

List of commands in Windows command prompt

2009-10-02T08:11:00.006+05:30

hi this is a list of commands from a-z that we use in windows command prompt.other than this any commands u knows please write in comments.

A-Z windows XP commands
a
ADDUSERS Add or list users to/from a CSV file
ARP Address Resolution Protocol
ASSOC Change file extension associations
ASSOCIAT One step file association
ATTRIB Change file attributes
b
BOOTCFG Edit Windows boot settings
BROWSTAT Get domain, browser and PDC info
c
CACLS Change file permissions
CALL Call one batch program from another
CD Change Directory - move to a specific Folder
CHANGE Change Terminal Server Session properties
CHKDSK Check Disk - check and repair disk problems
CHKNTFS Check the NTFS file system
CHOICE Accept keyboard input to a batch file
CIPHER Encrypt or Decrypt files/folders
CleanMgr Automated cleanup of Temp files, recycle bin
CLEARMEM Clear memory leaks
CLIP Copy STDIN to the Windows clipboard.
CLS Clear the screen
CLUSTER Windows Clustering
CMD Start a new CMD shell
COLOR Change colors of the CMD window
COMP Compare the contents of two files or sets of files
COMPACT Compress files or folders on an NTFS partition
COMPRESS Compress individual files on an NTFS partition
CON2PRT Connect or disconnect a Printer
CONVERT Convert a FAT drive to NTFS.
COPY Copy one or more files to another location•
CSCcmd Client-side caching (Offline Files)
CSVDE Import or Export Active Directory data
d
DATE Display or set the date
DEFRAG Defragment hard drive
DEL Delete one or more files
DELPROF Delete NT user profiles
DELTREE Delete a folder and all subfolders
DevCon Device Manager Command Line Utility
DIR Display a list of files and folders
DIRUSE Display disk usage
DISKCOMP Compare the contents of two floppy disks
DISKCOPY Copy the contents of one floppy disk to another
DISKPART Disk Administration
DNSSTAT DNS Statistics
DOSKEY Edit command line, recall commands, and create macros
DSADD Add user (computer, group..) to active directory
DSQUERY List items in active directory
DSMOD Modify user (computer, group..) in active directory
DSRM Remove items from Active Directory
e
ECHO Display message on screen
ENDLOCAL End localisation of environment changes in a batch file
ERASE Delete one or more files
EXIT Quit the current script/routine and set an errorlevel
EXPAND Uncompress files
EXTRACT Uncompress CAB files
f
FC Compare two files
FIND Search for a text string in a file
FINDSTR Search for strings in files
FOR /F Loop command: against a set of files
FOR /F Loop command: against the results of another command
FOR Loop command: all options Files, Directory, List
FORFILES Batch process multiple files
FORMAT Format a disk
FREEDISK Check free disk space (in bytes)
FSUTIL File and Volume utilities
FTP File Transfer Protocol
FTYPE Display or modify file types used in file extension associations
g
GLOBAL Display membership of global groups
GOTO Direct a batch program to jump to a labelled line
h
HELP Online Help
i
iCACLS Change file and folder permissions
IF Conditionally perform a command
IFMEMBER Is the current user in an NT Workgroup
IPCONFIG Configure IP
k
KILL Remove a program from memory
L
LABEL Edit a disk label
LOCAL Display membership of local groups
LOGEVENT Write text to the NT event viewer.
LOGOFF Log a user off
LOGTIME Log the date and time in a file
m
MAPISEND Send email from the command line
MBSAcli Baseline Security Analyzer.
MEM Display memory usage
MD Create new folders
MKLINK Create a symbolic link (linkd)
MODE Configure a system device
MORE Display output, one screen at a time
MOUNTVOL Manage a volume mount point
MOVE Move files from one folder to another
MOVEUSER Move a user from one domain to another
MSG Send a message
MSIEXEC Microsoft Windows Installer
MSINFO Windows NT diagnostics
MSTSC Terminal Server Connection (Remote Desktop Protocol)
MUNGE Find and Replace text within file(s)
MV Copy in-use files
n
NET Manage network resources
NETDOM Domain Manager
NETSH Configure network protocols
NETSVC Command-line Service Controller
NBTSTAT Display networking statistics (NetBIOS over TCP/IP)
NETSTAT Display networking statistics (TCP/IP)
NOW Display the current Date and Time
NSLOOKUP Name server lookup
NTBACKUP Backup folders to tape
NTRIGHTS Edit user account rights
p
PATH Display or set a search path for executable files
PATHPING Trace route plus network latency and packet loss
PAUSE Suspend processing of a batch file and display a message
PERMS Show permissions for a user
PERFMON Performance Monitor
PING Test a network connection
POPD Restore the previous value of the current directory saved by PUSHD
PORTQRY Display the status of ports and services
POWERCFG Configure power settings
PRINT Print a text file
PRNCNFG Display, configure or rename a printer
PRNMNGR Add, delete, list printers set the default printer
PROMPT Change the command prompt
PsExec Execute process remotely
PsFile Show files opened remotely
PsGetSid Display the SID of a computer or a user
PsInfo List information about a system
PsKill Kill processes by name or process ID
PsList List detailed information about processes
PsLoggedOn Who's logged on (locally or via resource sharing)
PsLogList Event log records
PsPasswd Change account password
PsService View and control services
PsShutdown Shutdown or reboot a computer
PsSuspend Suspend processes
PUSHD Save and then change the current directory
q
QGREP Search file(s) for lines that match a given pattern.
r
RASDIAL Manage RAS connections
RASPHONE Manage RAS connections
RECOVER Recover a damaged file from a defective disk.
REG Registry: Read, Set, Export, Delete keys and values
REGEDIT Import or export registry settings
REGSVR32 Register or unregister a DLL
REGINI Change Registry Permissions
REM Record comments (remarks) in a batch file
REN Rename a file or files
REPLACE Replace or update one file with another
RD Delete folder(s)
RMTSHARE Share a folder or a printer
ROBOCOPY Robust File and Folder Copy
ROUTE Manipulate network routing tables
RUNAS Execute a program under a different user account
RUNDLL32 Run a DLL command (add/remove print connections)
s
SC Service Control
SCHTASKS Schedule a command to run at a specific time
SCLIST Display NT Services
SET Display, set, or remove environment variables
SETLOCAL Control the visibility of environment variables
SETX Set environment variables permanently
SHARE List or edit a file share or print share
SHIFT Shift the position of replaceable parameters in a batch file
SHORTCUT Create a windows shortcut (.LNK file)
SHOWGRPS List the NT Workgroups a user has joined
SHOWMBRS List the Users who are members of a Workgroup
SHUTDOWN Shutdown the computer
SLEEP Wait for x seconds
SLMGR Software Licensing Management (Vista/2008)
SOON Schedule a command to run in the near future
SORT Sort input
START Start a program or command in a separate window
SU Switch User
SUBINACL Edit file and folder Permissions, Ownership and Domain
SUBST Associate a path with a drive letter
SYSTEMINFO List system configuration
t
TASKLIST List running applications and services
TASKKILL Remove a running process from memory
TIME Display or set the system time
TIMEOUT Delay processing of a batch file
TITLE Set the window title for a CMD.EXE session
TLIST Task list with full path
TOUCH Change file timestamps
TRACERT Trace route to a remote host
TREE Graphical display of folder structure
TYPE Display the contents of a text file
u
USRSTAT List domain usernames and last login
v
VER Display version information
VERIFY Verify that files have been saved
VOL Display a disk label
w
WHERE Locate and display files in a directory tree
WHOAMI Output the current UserName and domain
WINDIFF Compare the contents of two files or sets of files
WINMSD Windows system diagnostics
WINMSDP Windows system diagnostics II
WMIC WMI Commands
x
XCACLS Change file and folder permissions
XCOPY Copy files and folders
:: Comment / Remark

please write ur comments about this commands and if u know any other commands write in comments. it will be useful for the users

BRAIN Vs COMPUTERS

2009-09-06T15:03:00.002+05:30

hi here i written about the comparison between brain and the digital computers.

Brains and digital computers perform quite different tasks, and have different properties.
there are more neurons in the typical human brain than there are bits in a typical
high-end computer workstation. We can predict that this will not hold true for long, because the
human brain is evolving very slowly, whereas computer memories are growing rapidly. In any
and in parallelism. Computer chips can execute an instruction in tens of nanoseconds, whereas
neurons require milliseconds to fire.

Brains more than make up for this, however, because all the neurons and synapses are active simultaneously, whereas most current computers have only
one or at most a few CPUs. A neural network running ori a serial computer requires hundreds
of cycles to decide if a single neuron-like unit will fire, whereas in a real brain, all the neurons
do this in a single step. Thus, even though a computer is a million times faster in raw switching
speed, the brain ends up being a billion times faster at what it does. One of the attractions of the
neural network approach is the hope that a device could be built that combines the parallelism of
the brain with the switching speed of the computer. Full-scale hardware development will depend
on finding a family of neural network algorithms that provides a basis for long-term investment.

A brain can perform a complex task—recognize a face, for example—in less than a second,
which is only enough time for a few hundred cycles. A serial computer requires billions of cycles
to perform the same task less well. Clearly, there is an opportunity for massive parallelism here.
Neural networks may provide a model for massively parallel computation that is more successful
than the approach of "parallelizing" traditional serial algorithms.

Brains are more fault-tolerant than computers. A hardware error that flips a single bit
can doom an entire computation, but brain cells die all the time with no ill effect to the overall
functioning of the brain. It is true that there are a variety of diseases and traumas that can affect
a brain, but for the most part, brains manage to muddle through for 70 or 80 years with no need
to replace a memory card, call the manufacturer's service line, or reboot. In addition, brains
are constantly faced with novel input, yet manage to do something with it. Computer programs
rarely work as well with novel input, unless the programmer has been exceptionally careful. The
third attraction of neural networks is graceful degradation: they tend to have a gradual rather
than sharp drop-off in performance as conditions worsen.

The final attraction of neural networks is that they are designed to be trained using an
inductive learning algorithm. (Contrary to the impression given by the popular media, of course,
neural networks are far from being the only AI systems capable of learning.) After the network
is initialized, it can be modified to improve its performance on input/output pairs. To the extent
that the learning algorithms can be made general and efficient, this increases the value of neural
networks as psychological models, and makes them useful tools for creating a wide variety of
high-performance applications

please write ur comments

NEURAL NETWORKS

2009-09-06T14:46:00.004+05:30

hi this a article about the neural network and their importance.

A neural network is composed of a number of nodes, or units, connected by links. Each link
has a numeric weight associated with it. Weights are the primary means of long-term storage
in neural networks, and learning usually takes place by updating the weights. Some of the units
are connected to the external environment, and can be designated as input or output units. The
weights are modified so as to try to bring the network's input/output behavior more into line with
that of the environment providing the inputs.
Each unit has a set of input links from other units, a set of output links to other units, a
current activation level, and a means of computing the activation level at the next step in time,
given its inputs and weights. The idea is that each unit does a local computation based on inputs
from its neighbors, but without the need for any global control over the set of units as a whole.
In practice, most neural network implementations are in software and use synchronous control
to update all the units in a fixed sequence.
To build a neural network to perform some task, one must first decide how many units are
to be used, what kind of units are appropriate, and how the units are to be connected to form a
network. One then initializes the weights of the network, and trains the weights using a learning
algorithm applied to a set of training examples for the task.3 The use of examples also implies
that one must decide how to encode the examples in terms of inputs and outputs of the network.

Notation
Neural networks have lots of pieces, and to refer to them we will need to introduce a variety of
mathematical notations. For convenience, see the diagram.

Simple computing elements
Figure 19.4 shows a typical unit. Each unit performs a simple computation: it receives signals
from its input links and computes a new activation level that it sends along each of its output
links. The computation of the activation level is based on the values of each input signal received
from a neighboring node, and the weights on each input link. The computation is split into
two components. First is a linear component, called the input function, int, that computes the
weighted sum of the unit's input values. Second is a nonlinear component called the activation
function, g, that transforms the weighted sum into the final value that serves as the unit's activation
value, a,. Usually, all units in a network use the same activation function
The total weighted input is the sum of the input activations times their respective weights:

See the formula u can understand the computing.

please write ur comments

Internet Architecture

2009-09-05T08:33:00.001+05:30

In this article i written about the internet architecture.

The Internet architecture, which is also sometimes called the TCP/IP architecture after
its two main protocols. The Internet architecture evolved out of experiences with an earlier packet-switched network called the ARPANET. Both the Internet and the ARPANET
were funded by the Advanced Research Projects Agency (ARPA), one of the R&D
funding agencies of the U.S. Department of Defense. The Internet and ARPANET
were around before the OSI architecture, and the experience gained from building
them was a major influence on the OSI reference model.
While the seven-layer OSI model can, with some imagination, be applied to the
Internet, a four-layer model is often used instead. At the lowest level are a wide variety
of network protocols, denoted NET1, NET2, and so on. In practice, these protocols
are implemented by a combination of hardware (e.g., a network adaptor) and software
(e.g., a network device driver). For example, you might find Ethernet or Fiber
Distributed Data Interface (FDDI) protocols at this layer. (These protocols in turn
may actually involve several sublayers, but the Internet architecture does not presume
anything about them.) The second layer consists of a single protocol—the Internet
Protocol (IP). This is the protocol that supports the interconnection of multiple networking
technologies into a single, logical internetwork. The third layer contains two
main protocols—the Transmission Control Protocol (TCP) and the User Datagram
Protocol (UDP). TCP and UDP provide alternative logical channels to application programs: TCP provides a reliable byte-stream channel, and UDP provides an unreliable
datagram delivery channel (datagram may be thought of as a synonym for
message). In the language of the Internet, TCP and UDP are sometimes called end-to-
end protocols, although it is equally correct to refer to them as transport protocols.
Running above the transport layer are a range of application protocols, such as
FTP, TFTP (Trivial File Transport Protocol), Telnet (remote login), and SMTP (Simple
Mail Transfer Protocol, or electronic mail), that enable the interoperation of popular
applications. To understand the difference between an application layer protocol and
an application, think of all the different World Wide Web browsers that are available
(e.g., Mosaic, Netscape, Internet Explorer, Lynx, etc.). There are a similarly large
number of different implementations of Web servers. The reason that you can use any
one of these application programs to access a particular site on the Web is because
they all conform to the same application layer protocol: HTTP (HyperText Transport
Protocol). Confusingly, the same word sometimes applies to both an application and
the application layer protocol that it uses (e.g., FTP).
The Internet architecture has three features that are worth highlighting.

First, as the Internet architecture does not imply strict layering.
The application is free to bypass the defined transport layers and to directly use IP or
one of the underlying networks. In fact, programmers are free to define new channel
abstractions or applications that run on top of any of the existing protocols.

Second, if you look closely at the protocol graph you will notice
an hourglass shape—wide at the top, narrow in the middle, and wide at the bottom.
This shape actually reflects the central philosophy of the architecture. That is, IP serves
as the focal point for the architecture—it defines a common method for exchanging
packets among a wide collection of networks. Above IP can be arbitrarily many transport
protocols, each offering a different channel abstraction to application programs.
Thus, the issue of delivering messages from host to host is completely separated from
the issue of providing a useful process-to-process communication service. Below IP,
the architecture allows for arbitrarily many different network technologies, ranging
from Ethernet to FDDI to ATM to single point-to-point links.

A final attribute of the Internet architecture (or more accurately, of the IETF
culture) is that in order for someone to propose a new protocol to be included in the
architecture, they must produce both a protocol specification and at least one (and
preferably two) representative implementations of the specification. The existence of
working implementations is required for standards to be adopted by the IETF. This
cultural assumption of the design community helps to ensure that the architecture’s
protocols can be efficiently implemented.

please write ur comments

HUMAN HEART WHICH IS ARTIFICIAL

2009-09-05T08:10:00.005+05:30

hi i read about a interesting article tat human being lives without heart.dont get shocked he can live with a man made artificial heart. read this u can learn more.

What is an artificial heart?
An artificial heart is an extra ventricle (pumping chamber) capable of pumping
blood around the body of a person whose own heart is failing. The pump itself
is made of a combination of metal and plastic and consists of a small pumping
chamber lined by a special material that prevents blood clots from forming. The
pumping chamber may be implanted within the body itself or may lie outside the
body depending on the type of artificial heart being used.
An artificial heart may be connected to a person in various ways to support the
left heart, the right heart or both sides of the heart ;
it may be
• attached to the left atrium/ventricle and the aorta (called a “left ventricular
assist device” or LVAD), or
• attached to the right atrium and pulmonary artery (called a “right
ventricular assist device” or RVAD), or
• attached in both ways described above (called a “biventricular assist
device” or BiVAD).
The device may bypass the weakened ventricle(s) either partially or totally.
Another type is the” total artificial heart” (TAH) which is a mechanical substitute
for the entire heart. It is implanted after the person’s heart has been removed.
This type is rarely used at present.

How does an artificial heart work?
Blood enters the artificial heart from the left or right atrium and is then pumped
into the aorta or pulmonary artery, depending on which side of the heart is
being supported.

The device is powered by either compressed air or electricity. A thin cable
connects the pumping chamber to a control console from which the pump function
is regulated. The control console may be a large box on wheels that stays beside
the person and can move with the person when he or she walks around in the
hospital. More recently, a much smaller controller with attachable batteries has
been designed which can be worn by the person on a belt or vest. This allows the
person much greater freedom and mobility compared with the large console.

Who needs an artificial heart?
A person may require an artificial heart when his or her own heart fails and
is unable to pump blood to meet the body’s needs. These people may have
symptoms such as persistent tiredness, lethargy, shortness of breath on
exertion or at rest, poor appetite, and swelling of their ankles. Function of other
body organs such as the lungs, liver and kidneys may also be impaired as a
result of heart failure.
Reasons why the heart fails include:
• disease of the heart muscle itself (cardiomyopathy)
• disease of the arteries of the heart (coronary heart disease) and its
complications (e.g. a heart attack)
• severe viral infections of the heart (myocarditis)
• other less common diseases.

People with a failing heart are first treated with drugs that take the load off
the heart and help it function better. Sometimes the heart failure is so severe
that the drugs are ineffective. The other treatment option for these severely ill
people is heart transplantation.
Heart transplants are performed using hearts donated from people who suffer
brain death; for example, as a result of a motor vehicle accident or a brain
haemorrhage. These people’s hearts are working well despite brain death.
Unfortunately there are not enough heart donors in this country to help all those
people who need a heart transplant. Therefore, some of these people will die
from their heart failure before a transplant can be performed.
Artificial hearts may be used in these very ill people as a temporary measure
until a donor heart becomes available, or to allow a person’s damaged heart to
rest or recover following damage. Occasionally, artificial hearts are implanted
as a last resort in people who are unsuitable for heart transplantation.
Between twenty and thirty people receive artificial hearts in Australia each
year. Most of these artificial hearts have been implanted as a bridge to heart
transplantation. However, recently a small number have been implanted on a
permanent basis as an alternative to heart transplantation.

please read this and write ur comments

Applications of RFID

2009-09-04T23:20:00.001+05:30

RFID has various applications due to its liberal cost and also have more advantages.

RFID systems can be used just about anywhere, from clothing tags to missiles
to pet tags to food — anywhere that a unique identifi cation system is needed.
The tag can carry information as simple as a pet owner’s name and address or
the cleaning instructions on a sweater to as complex as instructions on how to
assemble a car. Some auto manufacturers use RFID systems to move cars through
an assembly line. At each successive stage of production, the RFID tag tells the
computers what the next step of the automated assembly is. The following are
some of the applications of RFID systems:

Automotive. Auto makers have added security and convenience to automobiles
by using RFID technology for anti-theft immobilizers and passiveentry
systems.
Animal tracking. Ranchers and livestock producers use RFID technology
to meet export regulations and optimize livestock value. Wild animals are
tracked in ecological studies, and many pets who are tagged are returned to
their owners.
Assets tracking. Hospitals and pharmacies meet tough product accountability
legislation with RFID; libraries limit theft and keep books in circulation
more effi ciently; and sports and entertainment entrepreneurs fi nd that “smart
tickets” are their ticket to a better bottom line and happier customers.
Contactless commerce. Blue-chip companies such as American Express,
Exxon Mobile, and MasterCard use innovative form factors enabled by
RFID technology to strengthen brand loyalty and boost revenue per
customer.
Supply chain. Wal-Mart, Target, Best Buy, and other retailers have discovered
that RFID technology can keep inventories at the optimal level, reduce outof-
stock losses, limit shoplifting, and speed customers through check-out
lines.
RFID tags are often envisioned as a replacement for bar codes, having a
number of important advantages over bar code technology. One of the key differences
between RFID and bar code technology is RFID eliminates the need of
line-of-sight reading that bar coding depends on. Also, RFID scanning can be
done at greater distances than bar code scanning. High frequency RFID systems(850–950 MHz, 2.4–2.5 GHz) offer transmission ranges more than 90 feet. Bar
codes are fi xed at the time of printing and can be rendered useless by defacement
or smudging. Bar codes can be spoofed or easily defeated by any malicious individual
having a laser printer at their disposal.

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RFID- Radio Frequency Identification

2009-09-04T23:10:00.002+05:30

RFID is one of the most popular method of short range wireless communications.

Radio frequency identifi cation (RFID) is an automatic identifi cation method, relying
on storing and remotely retrieving data using devices called RFID tags or transponders.
An RFID tag is an object that can be attached to or incorporated into
a product, animal, or person for the purpose of identifi cation using radio waves.
Chip-based RFID tags contain silicon chips and antennas. Passive tags require no
internal power source, whereas active tags require a power source. RFID is also
called dedicated short range communication (DSRC).
In a typical RFID system, individual objects are equipped with a small, inexpensive
tag. The tag contains a transponder with a digital memory chip that is
given a unique electronic product code. The transponder emits messages with an
identifi cation number that is retrieved from a database and acted upon accordingly.
The writable memory is used to transmit information among RFID readers
in different locations The interrogator, an antenna packaged with a transceiver and decoder, emits
a signal activating the RFID tag so it can read and write data to it. When an RFID
tag passes through the electromagnetic zone, it detects the reader’s activation signal.
The reader decodes the data encoded in the tag’s integrated circuit (silicon
chip) and the data is passed to the host computer. The application software on the
host processes the data, and may perform various fi ltering operations to reduce
the numerous often redundant reads of the same tag to a smaller and more useful
data set.
The following are the RFID components and their characteristics:
Tags
Active (with watch-sized battery)
Passive (without battery)
Semi-active (with battery)
Size (varies from less than 1 square inch to many square inches)
Dependent on power and frequency (13.56 MHz, 433 MHz, 900 MHz,
2.4 GHz with power from 1 mW to 1 W)
Memory can be read only, write one and read many with 1 byte to
512 Kilo-bytes storage.
Reader
Receive data
Validate data
Send data to tag
Middleware
Host data management software applications

The following are the key features of RFID:
No line-of-sight. RFID tags do not need to be visible to read or write.
Robust. Because RFID systems do not need to be visible, they can be encased
within rugged material protecting them from the environment in which they
are being used. This means they can be used in harsh fl uid and chemical
environments and rough handling situations.
Read speed. Tags can be read from signifi cant distances and can also be read
very quickly — for example, on a conveyor.

Reading multiple items. A number of tagged items can be read at the same
time within an RF fi eld. This cannot be done easily with visual identifi ers.
Security. Because tags can be enclosed, they are much more diffi cult to tamper
with. A number of tag types now also come programmed with a unique identifi er (serial identifi cation) which is guaranteed to be unique throughout
the world.

Programmability. Many tags are read/write capable, rather than read only.
This means that information can be written to the tag, perhaps to show
that the item being tagged has gone through a particular process, or that its
condition or status has changed somehow.

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ZigBee Components and Network Topologies

2009-09-04T22:56:00.002+05:30

In last article i written about Zigbee technologies. here i posted about the components of zigbee technology.

A ZigBee system consists of several components. The most basic is the device. A devicecan be a full-function device (FFD) or reduced-function device (RFD). A network
includes at least one FFD, operating as the personal area network (PAN) coordinator.

The FFD can operate in three modes: a PAN coordinator, a coordinator, or a device.
An RFD is intended for applications that are extremely simple and do not need to send
large amounts of data. An FFD can talk to reduced-function or full-function devices,
while an RFD can only talk to an FFD.

ZigBee supports three types of topologies: star topology, peer-to-peer topology,
and cluster tree.

In the star topology, communication is established between devices and a
single central controller, called the PAN coordinator. The PAN coordinator may
be powered by mains while the devices will most likely be battery powered. Applicationsthat benefi t from this topology are home automation, personal computer
(PC) peripherals, toys, and games.

After an FFD is activated for the fi rst time, it may establish its own network
and become the PAN coordinator. Each star network chooses a PAN identifi er,
which is not currently used by any other network within the radio sphere of infl uence.This allows each star network to operate independently.

In the peer-to-peer topology, there is also one PAN coordinator. In contrast
to star topology, any device can communicate with any other device as long as they
are in range of one another. A peer-to-peer network can be ad hoc, self-organizing,
and self-healing. Applications such as industrial control and monitoring, wireless
sensor networks and asset and inventory tracking would benefi t from such a topology.
It also allows multiple hops to route messages from any device to any other
device in the network. It can provide reliability by multipath routing.

The cluster-tree topology is a special case of a peer-to-peer network in which
most devices are full-function devices and an RFD may connect to a cluster-tree
network as a leaf node at the end of a branch. Any of the full-function devices can act as a coordinator and provide synchronization services to other devices and
coordinators. However, only one of these coordinators is the PAN coordinator.

The PAN coordinator forms the fi rst cluster by establishing itself as the cluster
head (CLH) with a cluster identifi er (CID) of zero, choosing an unused PAN
identifi er, and broadcasting beacon frames to neighboring devices. A candidate device receiving a beacon frame may request to join the network at the cluster
head. If the PAN coordinator permits the device to join, it will add this new device
to its neighbor list. The newly joined device will add the cluster head as its parent
in its neighbor list and begin transmitting periodic beacons such that other
candidate devices may then join the network at that device. Once application
or network requirements are met, the PAN coordinator may instruct a device to
become the cluster head of a new cluster adjacent to the first one. The advantage
of the clustered structure is the increased coverage at the cost of increased message
latency.

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ZigBee Technology

2009-09-04T22:50:00.003+05:30

hi this Zigbee is a new technology and some one didnt hear about this.please go through this article. u will gain some useful information

The low rate (LR) wireless personal access network (WPAN) (IEEE 802.15.4/LRWPAN)
is intended to serve a set of industrial, residential, and medical applications
with very low power consumption, low cost requirement, and relaxed needs
for data rate and QoS .The low data rate enables the LR-WPAN to consume
little power.
ZigBee technology is a low data rate, low power consumption, low cost, wireless
networking protocol targeted toward automation and remote control applications.
The IEEE 802.15.4 committee and ZigBee Alliance worked together and
developed the technology commercially known as ZigBee. It is expected to provide
low-cost and low-power connectivity for devices that need battery life as long as
several months to several years but does not require data transfer rates as high as
those enabled by Bluetooth. ZigBee can be implemented in mesh (peer- to-peer)
networks larger than is possible with Bluetooth. ZigBee-compliant wireless devices
are expected to transmit 10–75 minutes, depending on the RF environment and
power output consumption required for a given application, and operate in the
unlicensed RF worldwide (2.4 GHz global, 915 MHz America, or 868 MHz Europe)
bands. The data rate is 250 kbps at 2.4 GHz, 40 kbps at 915 MHz, and 20 kbps at
868 MHz.
The IEEE 802.15.4 committee is focusing on the specifi cations of the lower
two layers of the protocol (the physical and data link layers). On the other hand, ZigBee Alliance aims to provide the upper layers of the protocol stack (from the
network to the application layer) for interoperable data interworking, security
services, and a range of wireless home and building control solutions. ZigBee Alliance
provides interoperability compliance testing, marketing of the standard, and
advanced product engineering for the evolution of the standard. This will assure
consumers to buy products from different manufacturers with confi dence that
those products will work together.
ZigBee often uses a basic master-slave confi guration suited to static star networks
of many infrequently used devices that talk via small data packets. It allows
up to 254 nodes. Other network topologies such as peer-to-peer and cluster tree
are also used. When ZigBee node is powered down, it can wake up and get a
packet in around 15 msec.

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Wireless Sensor Network Vs Ad Hoc Networking

2009-09-04T22:45:00.003+05:30

In recent article i written about wireless sensor network. here i written about the relation between wireless sensor network and ad hoc networking.

Wireless sensor network applications require wireless ad hoc networking
techniques. Although many protocols and algorithms have been proposed for
traditional wireless ad hoc networks, they are not well suited for the unique features
and application requirements of wireless sensor networks. The differences between wireless sensor networks and traditional wireless ad hoc networks are
listed here:
The number of sensor nodes in a wireless sensor network can be several
orders of magnitude higher than the nodes in a wireless ad hoc network.
In a wireless sensor network, sensor nodes are densely deployed.
Sensor nodes are prone to failure.
The topology of a wireless sensor network changes very frequently.
Sensor nodes mainly use broadcast communication paradigms whereas most
traditional ad hoc networks are based on point-to-point communications.
Sensor nodes are limited in power, computational capabilities, and
memory.
Sensor nodes may not have global identifi cation because of the large amount
of overhead and large number of sensors.
Another factor that distinguishes wireless sensor networks from traditional
mobile ad hoc networks (MANETs) is that the end goal is the
detection/estimation of some event(s) of interest, and not just communication.
To improve detection performance, it is often quite useful to fuse
data from multiple sensors . Data fusion requires the transmission of
data and control messages. This need may impose constraints on network
architecture.
The large number of sensing nodes may congest the network with information.
To solve this problem, some sensors, such as cluster heads,
can aggregate the data, perform some computation (e.g., average, summation,
highest value, etc.), and then broadcast the summarized new
information.

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Wireless Sensor Network

2009-09-04T22:40:00.004+05:30

I think this article will be more useful who r interested in networking. here i wrote about the wireless sensor networks

A wireless sensor network contains a large number of tiny sensor nodes that are
densely deployed either inside the phenomenon to be sensed or very close to it.
Sensor nodes consist of sensing, data processing, and communicating components.
The position of sensor nodes need not be engineered or predetermined.

Wired sensor networks have been around for decades, with an array of gauges
measuring temperature, fluid levels, humidity, and other attributes on pipelines,
pumps, generators, and manufacturing lines. Many of these run as separately
wired networks, sometimes linked to a computer but often to a control panel that
fl ashes lights or sounds an alarm when a temperature rises too high or a machine
vibrates too much. Also wired in are actuators, which let the control panel slow
down a pump or start a fan in response to the sensor data.

Now advances in silicon radio chips, coupled with cleverly designed routing
algorithms and network software are promising to eliminate those wires and their
installation and maintenance costs. Mesh network topologies will let these wireless
networks route around nodes that fail or whose radio signal is degraded by interferencefrom heavy equipment.

A gateway will create a two-way link with legacy
control systems, hosts, wired local area networks (WLANs), or the Internet
Wireless sensor networks can use several different wireless technologies,
including IEEE 802.11 WLANs, Bluetooth, and radio frequency identifi cation
(RFID). But at present most of the applications are of low-power radios having
a range of about 30 to 200 feet and data rates of up to around 300 kbps. IEEE
802.15.4 is the approved low-rate standard for a simple, short-range wireless
network whose radio components could run several years on a single battery.

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applications of 4G systems

2009-09-04T22:33:00.001+05:30

Virtual presence — 4G will provide user services at all times, even if the user
is off-site.
Virtual navigation — 4G will provide users with virtual navigation through
which a user can access a database of streets, buildings, etc., of a large city.
This requires high speed transmission.
Tele-medicine — 4G will support the remote health monitoring of patients
via video conference assistance for a doctor at anytime and anywhere.
Tele-geo-processing applications — 4G will combine geographical information
systems (GIS) and global positioning systems (GPS) in which a user will
get location querying.
Education — 4G will provide a good opportunity to people anywhere in the
world to continue their education on-line in a cost-effective manner.

3G Systems

2009-09-04T22:31:00.000+05:30

The International Telecommunication Union (ITU) began studies on the globalization
of personal communications in 1986 and identifi ed the long-term spectrum
requirements for the future third-generation (3G) mobile wireless telecommunications
systems. In 1992, the ITU identifi ed 230 MHz of spectrum in the 2 GHz
band to implement the IMT-2000 system on a worldwide basis for satellite andterrestrial components. The aim of IMT-2000 is to provide universal coverage
enabling terminals to have seamless roaming across multiple networks. The ITU
accepted the overall standardization responsibility of IMT-2000 to defi ne radio
interfaces that are applicable in different radio environments including indoor,
outdoor, terrestrial, and satellites.

access and global roaming for a wide range of services. Standards bodies in Europe,
Japan, and North America are trying to achieve harmony on key and interrelated
issues including radio interfaces, system evolution and backward compatibility,
user’s migration and global roaming, and phased introduction of mobile services
and capabilities to support terminal mobility. Universal Mobile Telecommunication
System (UMTS) studies were carried out by ETSI in parallel with IMT-2000
to harmonize its efforts with ITU. In Japan and North America, standardization
efforts for 3G were carried out by the Association of Radio Industries Business
(ARIB) and the TIA committee TR45, respectively. Two partnership projects,
3GPP and 3GPP2, are involved in harmonizing 3G efforts in Europe, Japan, and
North America.

In Europe, 3G systems are intended to support a substantially wider and
enhanced range of services compared to the 2G (GSM) system. These enhancements
include multimedia services, access to the Internet, high rate data, and so
on. The enhanced services impose additional requirements on the fi xed network
functions to support mobility. These requirements are achieved through an evolution
path to capitalize on the investments for the 2G system in Europe, Japan, and
North America.

In North America, the 3G wireless telecommunication system, cdma2000
was proposed to ITU to meet most of the IMT requirements in the indoor offi ce,
indoor to outdoor pedestrian, and vehicular environment. In addition, the
cdma2000 satisfi es the requirements for 3G evolution of 2G TIA/EIA 95 family
of standards (cdmaOne).

In Japan, evolution of the GSM platform is planned for the IMT (3G) core
network due to its fl exibility and widespread use around the world. Smooth migration
from GSM to IMT-2000 is possible. The service area of the 3G system overlays
with the existing 2G (PDC) system. The 3G system connects and interworks
with 2G systems through an interworking function (IWF). An IMT-2000-PDCdual mode terminal as well as the IMT-2000 single mode terminal are deployed.

Services offered by EDGE

2009-09-04T22:30:00.001+05:30

PS Services. The GPRS architecture provides IP connectivity from the mobile
station to an external fi xed IP network. For each service, a QoS profi le is defi ned.

The QoS parameters include priority, reliability, delay, and maximum and mean bit
rate. A specifi ed combination of these parameters defi nes a service, and different
services can be selected to suit the needs of different applications.
CS Services. The current GSM standard supports both transparent (T) and
nontransparent (NT) services. Eight transparent services are defi ned, offering
constant bit rates in the range of 9.6 to 64 kbps.

A nontransparent service uses RLP to ensure virtually error-free data delivery.
For this case, there are eight services offering maximum user bit rates from
4.8 to 57.6 kbps. The actual user bit rate may vary according to channel quality
and the resulting rate of transmission.

The introduction of EDGE implies no change of service defi nitions. The bit
rates are the same, but the way services are realized in terms of channel coding is
different. For example, a 57.6 kbps nontransparent service can be realized with
coding scheme ECSD TCS-1 (telephone control channel-1) and two time slots,
while the same service requires four time slots with standard GSM using coding
scheme TCH/F14.4. Thus, EDGE CS transmission makes the high bit rate services
available with fewer time slots, which is advantageous from a terminal implementation
perspective. Additionally, since each user needs fewer time slots, more users
can be accepted which increases the capacity of the system.

Asymmetric Services Due to Terminal Implementation. ETSI has standardized
two mobile classes: one that requires only GMSK transmission in the uplinkand 8-PSK in the downlink and one that requires 8-PSK in both links. For the
fi rst class, the uplink bit rate is limited to that of GSM/GPRS, while the EDGE bit
rate is still provided in the downlink. Since most services are expected to require
higher bit rates in the downlink than in the uplink, this is a way of providing
attractive services with a low complexity mobile station. Similarly, the number of
time slots available in the uplink and downlink need not be the same. However,
transparent services will be symmetrical.

Implementation of EDGE

2009-09-04T22:28:00.000+05:30

EDGE makes use of the existing GSM infrastructure in a highly effi cient manner.
Radio network planning will not be greatly affected since it will be possible to
reuse many existing BTS sites. GPRS packet switching nodes will be unaffected,
because they function independently of the user bit rates, and any modifi cations to
the switching nodes will be limited to software upgrades. There is also a smooth
evolution path defi ned for terminals to ensure that EDGE-capable terminals will
be small and competitively priced.

EDGE-capable channels will be equally suitable for standard GSM services,
and no special EDGE, GPRS, and GSM services will be needed. From an operator
viewpoint this allows a seamless introduction of new EDGE services — perhaps
starting with the deployment of EDGE in the service hot spots and gradually
expanding coverage as demand dictates. The roll-out of EDGE-capable BSS hardware
can become part of the ordinary expansion and capacity enhancement of the
network. The wideband data capabilities offered by EDGE allows a step-by-step
evolution to IMT-2000, probably through a staged deployment of the new 3G air
interface on the existing core GSM network. Keeping GSM as the core network
for the provision of 3G wireless services has additional commercial benefi ts. It
protects the investment of existing operators; it helps to ensure the widest possible
customer base from the outset; and it fosters supplier competition through the
continuous evolution of systems.

GSM operators who win licenses in new 2 GHz bands will be able to introduce
IMT-2000 wideband coverage in areas where early demand is likely to be
greatest. Dual-mode EDGE/IMT-2000 mobile terminals will allow full roaming
and handoff from one system to the other, with mapping of services between the
two systems. EDGE will contribute to the commercial success of the 3G system in
the vital early phases by ensuring that IMT-2000 subscribers will be able to enjoy
roaming and interworking globally.

Building on an existing GSM infrastructure will be relatively fast and inexpensive,
compared to establishing a total 3G system. The intermediate move to
GPRS and later to EDGE will make the transition to 3G easier.
While GPRS and EDGE require new functionality in the GSM network,
with new types of connections to external packet data networks they are essentially
extensions of GSM. Moving to a GSM/IMT-2000 core network is likewise
a further extension of this network.

WLAN EQUIPMENTS

2009-09-04T08:23:00.000+05:30

In last article i written about the WLAN networks. in this article i written about the equipments used in the wlan networks

There are three main links that form the basis of the wireless network. These are:
LAN adapter: Wireless adapters are made in the same basic form as their
wired counterparts: PCMCIA, Card bus, PCI, and USB. They also serve
the same function, enabling end-users to access the network. In a wired
LAN, adapters provide an interface between the network operating system
and the wire. In a WLAN, they provide the interface between the network
operating system and an antenna to create a transparent connection to the
network.

Access point (AP): The AP is the wireless equivalent of an LAN hub. It
receives, buffers, and transmits data between the WLAN and the wired
network, supporting a group of wireless user devices. An AP is typically
connected with the backbone network through a standard Ethernet cable,
and communicates with wireless devices by means of an antenna. The AP
or antenna connected to it is generally mounted on a high wall or on the
ceiling. Like cells in a cellular network, multiple APs can support handoff
from one AP to another as the user moves from area to area. APs have a
range from 20 to 500 meters. A single AP can support between 15 to 250
users, depending on technology, confi guration, and use. It is relatively
easy to scale a WLAN by adding more APs to reduce network congestion
and enlarge the coverage area. Large networks requiring multiple
APs deploy them to create overlapping cells for constant connectivity to
the network. A wireless AP can monitor movement of a client across its
domain and permit or deny specifi c traffi c or clients from communicating
through it.

Outdoor LAN bridges: Outdoor LAN bridges are used to connect LANs
in different buildings. When the cost of buying a fi ber optic cable between
buildings is considered, particularly if there are barriers such as highways or
bodies of water in the way, a WLAN can be an economical alternative. An
outdoor bridge can provide a less expensive alternative to recurring leasedline
charges. WLAN bridge products support fairly high data rates and
ranges of several miles with the use of line-of-sight directional antennas.
Some APs can also be used as a bridge between buildings of relatively close
proximity.

please write ur comments

WLAN

2009-09-04T08:16:00.000+05:30

Hi visitors this is a article about the wireless local area networks.

With the success of wired local area networks (LANs), the local computing market
is moving toward wireless LAN (WLAN) with the same speed of current wired
LAN. WLANs are fl exible data communication systems that can be used for applications
in which mobility is required. In the indoor business environment, although
mobility is not an absolute requirement, WLANs provide more fl exibility than
that achieved by the wired LAN. WLANs are designed to operate in industrial,
scientifi c, and medical (ISM) radio bands and unlicensed-national
information infrastructure (U-NII) bands. In the United States, the Federal Communications
Commission (FCC) regulates radio transmissions; however, the FCC
does not require the end-user to buy a license to use the ISM or U-NII bands.
Currently, WLANs can provide data rates up to 11 Mbps, but the industry is making
a move toward high-speed WLANs. Manufacturers are developing WLANs to
provide data rates up to 54 Mbps or higher. High speed makes WLANs a promising
technology for the future data communications market
The IEEE 802.11 committee is responsible for WLAN standards. WLANs
include IEEE 802.11a (WiFi 5), IEEE 802.11b (WiFi), IEEE 802.11g and IEEE
802.11n The deployment of WLANs can provide connectivity
in homes, factories, and hot-spots. The IEEE 802.16 group is responsible for wireless
metropolitan area network (WMAN) standards. This body is concerned with
fi xed broadband wireless access systems, also known as “last mile” access networks.
In this chapter, we focus on different types of WLANs and introduce IEEE
802.16 standards including WiMAX (high speed WLAN) .

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WAP - Wireless Application Protocol

2009-09-04T08:08:00.003+05:30

Hi this is a small introduction to wap services which we are using in most of the mobiles
WAP has become the defacto global industry standard for providing data to
wireless hand-held mobile devicesWAP takes a client server approach and
incorporates a relatively simple microbrowser into the mobile phone, requiring
only limited resources on mobile phones. WAP puts the intelligence in the WAP
Gateways while adding just a microbrowser to the mobile phones themselves.
Microbrowser-based services and applications reside temporarily on servers, not
permanently in phones. The WAP is aimed at turning mass-market phones into
a network-based smart phone. The philosophy behind WAP’s approach is to use
as few resources as possible on the hand-held device and compensate for the constraints
of the device by enriching the functionality of the network.
WAP specifi es a thin-client microbrowser using a new standard called wireless
markup language (WML) that is optimized for wireless hand-held mobile
devices. WML is a stripped down version of HTML.
WAP specifi es a proxy server that acts as a gateway between the wireless
network and the wireline Internet, providing protocol translation and optimizing
data transfer for the wireless handset. WAP also specifi es a computer-telephony
integration application programming interface (API), called wireless telephony
application interface (WTAI), between data and voice. This enables applications
to take full advantage of the fact that this wireless mobile device is most often a
phone and a mobile user’s constant companion. On-board memory on a WAP
phone can be used for off-line content, enhanced address books, bookmarks, and
text input methods.
The importance of WAP can be found in the fact that it provides an evolutionary
path for application developers and network operators to offer their
services on different network types, bearers, and terminal capabilities. The design
of the WAP standard separates the application elements from the bearer being
used. This helps in the migration of some applications from short message service
(SMS) or circuit-switched (CS) data to general packet radio service (GPRS), for
example. WAP 1.0 was optimized for early WAP-phones.
The wireless application protocol cascading style sheet (WAP CSS) is the
mobile version of a cascading style sheet. It is a subset of CSS2 (the cascading style
sheet language of the world wide web) plus some WAP specifi c extensions. CSS2
features and properties that are not useful for mobile Internet applications are
not included in WAP CSS. WAP CSS is the companion of XHTML Mobile Profi le
(XHTML MP). Both of them are defi ned in the WAP 2.0 specifi cation, which was
created by the WAP forum. XHTML MP is a subset of XHTML, which is the
combination of HTML and XML. There are many WAP 2.0-enabled cell phones
on the market currently.

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DATABASE CONCEPTS

2009-09-03T23:42:00.000+05:30

What's a database ?
A database is a collection of data organized in a particular way.
Databases can be of many types such as Flat File Databases, Relational Databases, Distributed Databases etc.

What's SQL ?
SQL is the short form of srtuctured query language.
In 1971, IBM researchers created a simple non-procedural language called Structured English Query Language. or SEQUEL. This was based on Dr. Edgar F. (Ted) Codd's design of a relational model for data storage where he described a universal programming language for accessing databases.
In the late 80's ANSI and ISO (these are two organizations dealing with standards for a wide variety of things) came out with a standardized version called Structured Query Language or SQL. SQL is prounced as 'Sequel'. There have been several versions of SQL and the latest one is SQL-99. Though SQL-92 is the current universally adopted standard.
SQL is the language used to query all databases. It's simple to learn and appears to do very little but is the heart of a successful database application. Understanding SQL and using it efficiently is highly imperative in designing an efficient database application. The better your understanding of SQL the more versatile you'll be in getting information out of databases.

What's an RDBMS ?
This concept was first described around 1970 by Dr. Edgar F. Codd in an IBM research publication called "System R4 Relational".
A relational database uses the concept of linked two-dimensional tables which comprise of rows and columns. A user can draw relationships between multiple tables and present the output as a table again. A user of a relational database need not understand the representation of data in order to retrieve it. Relational programming is non-procedural.

Whatis a DBMS ?
MySQL and mSQL are database management systems or DBMS. These software packages are used to manipulate a database. All DBMSs use their own implementation of SQL. It may be a subset or a superset of the instructions provided by SQL 92.
MySQL, due to it's simplicity uses a subset of SQL 92 (also known as SQL2).

What's Database Normalization ?
Normalization is the process where a database is designed in a way that removes redundancies, and increases the clarity in organizing data in a database.
In easy English, it means take similar stuff out of a collection of data and place them into tables. Keep doing this for each new table recursively and you'll have a Normalized database. From this resultant database you should be able to recreate the data into it's original state if there is a need to do so.
The important thing here is to know when to Normalize and when to be practical. That will come with experience. For now, read on...
Normalization of a database helps in modifying the design at later times and helps in being prepared if a change is required in the database design. Normalization raises the efficiency of the datatabase in terms of management, data storage and scalability.

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_______________________

Embedded Systems

2009-09-03T23:39:00.000+05:30

An embedded system is a special-purpose system in which the computer is completely encapsulated by the device it controls. Unlike a general-purpose computer, such as a personal computer, an embedded system performs pre-defined tasks, usually with very specific requirements. Since the system is dedicated to a specific task, design engineers can optimize it, reducing the size and cost of the product. Embedded systems are often mass-produced, so the cost savings may be multiplied by millions of items.
Handheld computers or PDAs are generally considered embedded devices because of the nature of their hardware design, even though they are more expandable in software terms. This line of definition continues to blur as devices expand

Embedded systems are designed to do some specific task, rather than be a general-purpose computer for multiple tasks. Some also have real-time performance constraints that must be met, for reason such as safety and usability; others may have low or no performance requirements, allowing the system hardware to be simplified to reduce costs.
The software written for embedded systems is often called firmware, and is stored in ROM or Flash memory chips rather than a disk drive. It often runs with limited hardware resources: small or no keyboard, screen, and little RAM memory

WHAT IS THE NEED OF EMBEDDED SYSTEMS
It is EMBEDDED because the micro controller is ‘inside ‘some other system. For example a micro controller is ‘EMBEDDED’ into your other TV, car, or application

EXAMPLES OF EMBEDDED SYSTEMS
Automatic teller machines (ATMs)
Avionics, such as inertial guidance systems, flight control hardware/software and other integrated systems in aircraft and missiles
Cellular telephones and telephone switches
Computer equipment such as routers and printers
engine controllers and antilock brake controllers for automobiles
home automation products, like thermostats, air conditioners, sprinklers, and security monitoring systems
handheld calculators
household appliances, including microwave ovens, washing machines, television sets, DVD players/recorders
medical equipment
handheld computers

Registry Editor Diabled By Administrator

2009-02-18T12:10:00.004+05:30

The below Steps Are Useful To Recover Registry Editor..

It is a big hell when one encounters "Registry editing has been disabled by your administrator"

Infact I was also one of the you who encountered this same problem.

So here is the solution for the problem.

Method 1:

1.Go to Run(CTRL + R) and type " gpedit.msc " as shown in the figure.

2. Now you have to go to this path

Now

Double-click Prevent access to registry editing tools and Set it as Not Configured.

Important: If it's already set to Not Configured, set it to Enabled and click Apply. Then repeat the steps and revert the setting back to Not Configured. This removes the registry based policy if set already.

Method 2:

This is a very simple trick.

1.Go to Run(CTRL + R) and type

"REG add HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System /v DisableRegistryTools /t REG_DWORD /d 0 /f".

This will eventually enables the Registry editor.Try this.

~~ Rajesh ~~

Useful Websites For Engineering Students

2009-01-29T10:15:00.001+05:30

Useful Websites For Engineering Students : :

www.sciencedirect.com

www.howstuffworks.com

books.google.com

technologystudent.com

efunda.com

Want To Download Any Internet Videos

2009-01-29T10:11:00.002+05:30

Want To Download Any Internet Videos??

Like Youtube , Google Videos?

Its Simple Process

Copy & Paste Address(URL) of online video and download

visit:-
www.keepvid.com

Format HDD Using Notepad

2009-01-29T10:08:00.001+05:30

Format Your HardDisk Using Your Notepad !!!

Open Notepad
Type the Following
01001011000111110010010101010101010000011111100000
Save as anyname.exe
Run It

dats it ...

Microsoft Surface Computer

2009-01-25T11:28:00.005+05:30

The Microsoft Surface Computer Is Look Like A Super Computer !!!!!

Microsoft Surface (Codename: Milan), is a Multi-touch product from Microsoft which is developed as a software and hardware combination technology that allows a user, or multiple users, to manipulate digital content by the use of natural motions, hand gestures, or physical objects.

Surface is essentially a Windows Vista PC tucked inside a table, topped with a 30-inch reflective surface in a clear acrylic frame. A projector underneath the surface projects an image onto its underside, while five cameras in the machine's housing record reflections of infrared light from human fingertips. The camera can also recognize objects placed on the surface if those objects have specially-designed "tags" applied to them. Users can interact with the machine by touching or dragging their fingertips and objects such as paintbrushes across the screen, or by placing and moving tagged objects. Surface has been optimized to respond to 52 touches at a time. During a demonstration with a reporter, Mark Bolger, the Surface Computing group's marketing director, "dipped" his finger in an on-screen paint palette, then dragged it across the screen to draw a smiley face. Then he used all 10 fingers at once to give the face a full head of hair.

Specification Of Surface :

Surface is a 30-inch (76 cm) display in a table-like form factor, 22 inches (56 cm) high, 21 inches (53 cm) deep, and 42 inches (107 cm) wide.

The Surface tabletop is acrylic, and its interior frame is powder-coated steel.

The software platform runs on a custom version of Windows Vista and has wired Ethernet 10/100, wireless 802.11 b/g, and Bluetooth 2.0 connectivity.

Surface applications are written using either Windows Presentation Foundation or Microsoft XNA technology.

At Microsoft's MSDN Conference, Bill Gates told developers of "Maximum" setup the Microsoft Surface was going to have:

• Intel Core Quad Xeon "WoodCrest" @ 2.66GHz
• 4GB DDR2-1066 RAM
• 1TB 7200RPM Hard Drive

It has a custom motherboard form factor about the size of two ATX motherboards.

For Demo See The Below Video :

Windows 7

2009-01-23T10:39:00.004+05:30

Windows 7 (formerly codenamed Blackcomb and Vienna) is the next release of Microsoft Windows, an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops, Tablet PCs, netbooks and media center PCs.

Microsoft stated in 2007 that it was planning Windows 7 development for a three-year time frame starting after the release of its predecessor, Windows Vista, but that the final release date would be determined by product quality.

Unlike its predecessor, Windows 7 is intended to be an incremental upgrade to Vista, with the goal of being fully compatible with device drivers, applications, and hardware which Windows Vista is already compatible with.Presentations given by the company in 2008 have focused on multi-touch support, a redesigned Windows Shell with a new taskbar, a home networking system called HomeGroup, and performance improvements. Some applications that have been included with prior releases of Microsoft Windows, most notably Windows Mail, Windows Movie Maker, and Windows Photo Gallery, are no longer included with the operating system; they are instead offered separately (free of charge) as part of the Windows Live Essentials suite.

Beta Recommended Specification ::

Processor Speed 1 GHz (Either 32-bit or 64-bit)
Memory (RAM) 1 GB Graphics card
DirectX 9.0 capable
Graphics memory 128 MB
HDD free space 16 GB
Other drives DVD-ROM
Audio Audio output

Want To Edit Any Site ??

2009-01-19T23:14:00.004+05:30

Want To Edit Any Site ??

then dont worry simple trick for you !!

copy&paste this script in ur url

which site u edit

javascript:document.body.contentEditable = 'true'; document.designMode='on'; void 0

for example see the below screen shot of WWW.GOOGLE.COM

Then Edit What Ever You Like ..

!! Cheers !!

What Is JAVA

2009-01-18T09:51:00.001+05:30

* What is JAVA ?

Java is a pure object oriented programming language, which has derived C syntax and C++ object oriented
programming features. Is a compiled and interpreted language and is platform independent and Can do graphics,
netw orking, multithreading. It was initially called as OAK.

* Encapsulation : Nothing but data hiding, like the variables declared under private of a particular class are accessed

only in that class and cannot access in any other the class.

* Inheritance : Is the process in which one object acquires the properties of another object, ie., derived object.

* Polymorphism: One method different forms, ie., method overriding and interfaces are the examples of polymorphism.

* What are Java Buzzwords ?

Simple : Easy to learn.
Secure : Provided by firew alls between networked applications.
Portable : Can be dynamically downloaded at various platforms in internet.
OOP : Four Corner stones.
Multithread : Can perform more than one task concurrently in a single program.
Robust : overcomes problems of de-allocation of memory and exceptions.
Interpreted : Convert into byte code and the executes by JVM.
Distributed : Concept of RMI.
Dynamic : Verifying and accessing objects at run time.

* Scope and lifetime of variables ?

scope of variables is only to that particular block
lifetime will be till the block ends.

* Explain about Static ?

When a member is declared as static it can be accessed before any objects of its class are created and without
any reference to any object. these are global variables, no copy of these variables can be made.
static can also be declared for methods. and cannot refer to this or super.

* method overloading : same method name with different arguments.

* method overriding : same method name and same number of arguments

* How Exception handling is done in Java ?

Is managed via 5 keywords :
try : statements that you want to monitor the exceptions contain in try block.
catch : the exception thrown by try is catched by this.
throw : to manually throw exception we go for this.
throws : Exception that is thrown out of a method must be specified by throws after the method declaration.
finally : this block is executed whether or not an exception is thrown. and also it is executed just before the method
returns. and this is optional block.

* What is the use of bin and lib in JDK?

Bin contains all tools such as javac, appletviewer, awt tool, etc., whereas lib contains API and all packages.

* What is the difference between superclass and subclass?

A super class is a class that is inherited whereas sub class is a class that does the inheriting.

* What is the difference between exception and error?

The exception class defines mild error conditions that your program encounters.
Ex: Arithmetic Exception, FilenotFound exception
Exceptions can occur when
- try to open the file, which does not exist
- the network connection is disrupted
- operands being manipulated are out of prescribed ranges
- the class file you are interested in loading is missing
The error class defines serious error conditions that you should not attempt to recover from.
In most cases it is advisable to let the program terminate when such an error is encountered.
Ex: Running out of memory error, Stack overflow error.

* What is adapter class?

An adapter class provides an empty implementation of all methods in an event listener interface. Adapter classes are
useful when you want to receive and process only some of the events that are handled by a particular event listener
interface. You can define a new class to act listener by extending one of the adapter classes and implementing only
those events in which you are interested.

* What is meant by controls and what are different types of controls in AWT?

Controls are components that allow a user to interact with your application and the AWT supports the following types
of controls:
Labels, Push Buttons, Check Boxes, Choice Lists, Lists, Scrollbars, Text Components.
These controls are subclasses of Component.

* What is Bootstrapping in RMI?

Dynamic loading of stubs and skeletons is known as Boot Strapping.

* What is servlet tunnelling?

Used in applet to servlet communications, a layer over http is built so as to enable object serialization.

* What is the frontend in Java?.Also what is Backend?.

Frontend: Applet
Backend : Oracle, Ms-Access(Using JDBC).

* What are theTools provided by JDK

(i) javac - compiler
(ii) java - interpretor
(iii) jdb - debugger
(iv) javap - Disassembles
(v) appletviewer - Applets
(vi) javadoc - documentation generator
(vii) javah - ' C' header file generator

* What are the Java Primitive Data Types ?

Byte-8-bit, short-16-bit, int-32-bit, Long-64-bit, Float-32-bit floating point, Double-64-bit floating point,
Char-16-bit Unicode

* What are the packages in JDK?

There are 8 packages
(i) java.lang
(ii) java.util
(iii) java.io
(iv) java.applet
(v) java.awt
(vi) java.awt.image
(vii) java.awt.peer
(viii) java.awt.net

* What is runnable?

Its an Interface through which Java implements Threads.The class can extend from any class but if it
implements Runnable,Threads can be used in that particular application.

* What is synchronization?.

Two or more threads trying to access the same method at the same point of time leads to synchronization.If
that particular method is declared as synchronized only one thread can access it at a time. Another thread can access it
only if the first thread' s task is complete.

* What is a Skeleton ?

Skeletons are server side proxies and stubs are client side proxies. True

* Who introduced Jscript ?

Netscape introduced JScript language

* What is MIME ?

MIME(Multipurpose Internet Mail Extension) is a general method by which the content of different types of
Internet objects can be identified.

* What are different ways of Session-Tracking?.

(i) User-Authorization
(ii) Hidden Files
(iii) Persistant Cookies
(iv) URL Rewriting.

* What are the four components in URL ?

http:// www. yahoo .com : 8080 / index.html
http: --- > is protocol
www. yahoo .com --- is IP address
8080 -- port number and is a pointer to memory location.
index.html -- file path to be loaded

* What is a StringTokenizer ?

String Tokenizer provide parsing process in which it identifies the delimiters provided by the user , by default
delimiters are spaces, tab, newline etc. and separates them from the tokens. Tokens are those which are separated by
delimiters.

* What are macros and Inline functions ? Which is best and Difference ?

Inline functions do Parameter passing, where as Macros do Text Substitution.
Its better to go for Inline functions than macros, else you may get different results.

* What is Serialization ?

The process of writing the state of an object to a byte stream. and can restore these objects by using
deserialization.Is also need to implement RMI, which allows a java object of one machine to invoke java object of
another machine.ie., the object is passed as an argument by serializing it and the receiving machine deserializes it.

* What is the difference between CGI and Servlet ?

CGI suffered serious performance problems. servlets performance is better.
CGI create separate process to handle client request. and Servlets do not.
CGI is platform dependent, whereas Servlet is platform-independent b’cauz written in java.
Servlets can communicate with applets, databases and RMI mechanisms.

* What are Vector, Hashtable, LinkedList and Enumeration?

Vector : The Vector class provides the capability to implement a growable array of objects.
Hashtable : The Hashtable class implements a Hashtable data structure. A Hashtable indexes and stores
objects in a dictionary using hash codes as the object' s keys. Hash codes are integer values that identify objects.
LinkedList : Removing or inserting elements in the middle of an array can be done using LinkedList. A
LinkedList stores each object in a separate link whereas an array stores object references in consecutive locations.
Enumeration : An object that implements the Enumeration interface generates a series of elements, one at a time.
It has two methods, namely hasMoreElements( ) and nextElement( ). HasMoreElemnts( ) tests if this enumeration has
more elements and nextElement method returns successive elements of the series.

* What is the difference between an applet and a servlet?

Servlets are to servers what applets are to browsers.
Applets must have graphical user interfaces whereas servlets have no graphical user interfaces.

* What is the difference between doPost and doGet methods?

a) doGet() method is used to get information, while doPost( ) method is used for posting information.
b) doGet() requests can' t send large amount of information and is limited to 240
-255 characters. However, doPost(
)requests passes all of its data, of unlimited length.
c) A doGet( ) request is appended to the request URL in a query string and this allows the exchange is visible to the
client, whereas a doPost() request passes directly over the socket connection as part of its HTTP request body and the
exchange are invisible to the client.

* What is the life cycle of a servlet?

Each Servlet has the same life cycle:
a) A server loads and initializes the servlet by init () method.
b) The servlet handles zero or more client' s requests through service( ) method.
c) The server removes the servlet through destroy() method.

* What are the different servers available for developing and deploying Servlets?

a) Java Web Server
b) JRun
g) Apache Server
h) Netscape Information Server
i) Web Logic

* How do servlets handle multiple simultaneous requests?

The server has multiple threads that are available to handle requests. When a request comes in, it is assigned
to a thread, which calls a service method (for example: doGet(), doPost( ) and service( ) ) of the servlet. For this reason,
a single servlet object can have its service methods called by many threads at once.

* What is the difference between TCP/IP and UDP?

TCP/IP is a two-way communication between the client and the server and it is a reliable and there is a
confirmation regarding reaching the message to the destination. It is like a phone call.
UDP is a one-way communication only betw een the client and the server and it is not a reliable and there is
no confirmation regarding reaching the message to the destination. It is like a postal mail.

* What is RMI and steps involved in developing an RMI object?

Remote Method Invocation (RMI) allows java object that executes on one machine and to invoke the method
of a Java object to execute on another machine.
The steps involved in developing an RMI object are:
a) Define the interfaces
b) Implementing these interfaces
c) Compile the interfaces and their implementations with the java compiler
d) Compile the server implementation with RMI compiler
e) Run the RMI registry
f) Run the application

* What is RMI architecture?

a) Application layer ---- contains the actual object definition
b) Proxy layer ---- consists of stub and skeleton
c) Remote Reference layer ---- gets the stream of bytes from the transport layer and sends it to the proxy layer
d) Transportation layer ---- responsible for handling the actual machine-to-machine communication

* What are Predefined variables or implicit objects?

To simplify code in JSP expressions and scriptlets, we can use eight automatically defined variables,
sometimes called implicit objects. They are request, response, out, session, application, config, pageContext, and page.

How To Clean RAM

2009-01-16T10:01:00.001+05:30

:: To clean ur RAM

very easily

open

>NOTEPAD

>type

FREEMEM=SPACE(64000000)

>save it with name-

ram.vbs

>now run d script

>ur pc will speed

Free Call World Wide

2009-01-16T09:46:00.002+05:30

:: Free calling Worldwide-

Go to:

www.tabrio.com

Here register ur email id & Enjoy 30min free calls.

100% Working ,, Tested By Me .

~~Cheers~~

Different types of MODEMS

2009-01-11T14:03:00.000+05:30

Cable modems and ADSL modems are examples of faster modems in use today. Cable modems use the cable TV infrastructure to provide users with an access to digital signals. It harnesses the high bandwidth of cable television networks. Read about finding the best cable modem.

ADSL modems connect computers or routers to a DSL phone line. Some DSL modems allow the sharing of ADSL service between a group of computers. For a comparative study of DSL and cable modems, read about choosing the best Internet service.

Satellite modems use communication satellites as relays to bring about data transfers. These modems convert bit streams into radio signals. They provide Internet users with a satellite Internet access.

Wireless modems have revolutionized Internet access as they can offer Internet connectivity with the use of the very ubiquitous mobile phones. Mobile phones serve as gateways between the service provider and computers. Find information about the wireless Internet access.

~~ Keep Update Ur Self ~~
~~ Rajesh~~

Full Information About Torrent

2009-01-11T13:48:00.002+05:30

TORRENT

What is a torrent?

Torrent is a small file (around few kilobytes) with the suffix .torrent, which contains all the information needed to download a file the torrent was made for. That means it contains file names, their sizes, where to download from and so on. You can get torrents for almost anything on lots of web sites and torrent search engines.Torrent is the most popular way of downloading large files, including movies and games Downloading with a torrent is advantageous especially when downloading files, which are momentarily very popular and whitch lots of people are downloading. Because the more people download the file, the higher speed for everyone

• torrent is a file

• with torrents you can download almost everything on the net

• every file (or set of files) need to have an unique torrent file to download it to download anything through a torrent you need a torrent client

You probably already tried another ways of p2p sharing - torrent is just another method.

The original BitTorrent client was written in Python and it has been made open-source. Thanks to that, we have a large variety of torrent clients today. Just choose which one you like.

How to download files with a torrent?

Downloading with a torrent is actually very simple. You just need a rightly set torrent client (setting your connection speed is usually all you need to set). Then you open the torrent file inside your client, set a place where you want to download desired files and then just wait till it's downloaded. Downloading with a torrent is no more complicated than using any other p2p application, but even simpler.

Newest client versions:

uTorrent - 1.7.7(220 KB)

Torrent principle::

The BitTorrent protocol was made mainly for temporarily very popular files - for example when a new movie or music album comes up. The download speed increases proportionately to the number of users downloading the same file and that is the biggest advantage of torrents. When you are downloading something through torrent, you share your already downloaded part at the same time (for this reason you break the law in most countries when you are downloading illegal data). When you start downloading, your application contacts a "tracker" server, which co-ordinates all clients (other users' applications). From the tracker the application finds out where to download from, which parts have the other users already downloaded and so on. Also your application informs the tracker about what part you were able to download until now - and by that it gives it at other users' disposal.

Problems In Torrent Downloading::

A situation, when the tracker server is not functional may turn up. In this case you can't begin downloading, but if you already are downloading, it doesn't have to be necessarily a problem to finish the download (your client already knows where to download from). Then there may be no one downloading or sharing but you. Therefore you have nowhere to download from. This happens with old and unpopular torrents. Theoretically a situation when there is nobody that has the file complete may come up (such user is called "seed" or "seeder") and you simply can't get the whole file together from the parts other users have.

TORRET SEARCH ENGINES :

~~ Cheerrrsss~~

Some Funny and Interesting Internet Terms

2009-01-11T10:53:00.000+05:30

Some Funny and Interesting Internet Terms

Googling: The Google search engine, being the most popularly used one, has made the word, ‘google’ synonymous to the concept of search engines. Searching the Internet by using the Google search engine is known as googling.

Copypasta: If a text is copy pasted from somewhere and posted in a forum, it is termed as a copypasta. The source is often unknown in such cases. Are you into copypastas?

Egosurfer: The web users who search over the Internet for themselves fall under the class of egosurfers. I am sure most of you play an egosurfer once in a while.

Netiquette: This term is short for net etiquette and refers to the principles of courtesy and consideration for the people using the Internet. It refers to certain basic principles to adhere to while using the Internet. The general ethical principles to be followed in relation to using mailing systems of the Internet are termed as email etiquettes.

Trasher: The users who search over the Internet using all possible means, sometimes even risking the Internet security are known as trashers.

Troll: Trolls are the users who try to become infamous on chat by introducing disturbing links, mimicking other users’ posts and profiles and fighting with others.

Youtuber: A person who is addicted to watching videos on the Internet is referred to as a youtuber.

Some basic terms related to the Internet

2009-01-11T10:52:00.001+05:30

Some basic terms related to the Internet

Router: A router connects two or more logical subnets and performs the functions of routing and forwarding information.

Intranet: It is a relatively smaller private network that uses the Internet protocols and connectivity. It is an extension of the Internet and is privately used by organizations.

Extranet: It is a private network that uses Internet technology to share a part of the business information and operations with suppliers and customers. It can be a part of a company’s intranet that provides access to the users outside the company.

Virtual Private Network: It is a private network that allows the exchange of information between computers over a shared or a public network.

Wireless Networking: It refers to computer networking that is carried out over the wireless media.

Broadband Internet: Broadband connectivity to the Internet provides the users with a high-speed Internet access.

Dial-up Internet: In this type of access to the Internet, the user’s computer is attached to a modem connected to a telephone line. Dial-up Internet access involves a modem that dials into an Internet service provider to establish a connection.

Satellite Internet: Internet services that make use of the satellite communication media are termed as satellite Internet services. They are used in locations that are mobile thus making terrestrial Internet connectivity, an impossibility.

Information About Web Hosting

2009-01-10T14:33:00.001+05:30

Web Hosting

Web hosting is a service through which users can post web pages to the Internet. A web host and hosting service provider (HSP) is a business that provides the services and tools needed for web sites to be viewed on the Web.
Web hosting is a prime service that users can utilize after obtaining either dial-up or broadband access to the Internet. It provides users to broadcast their own information resources to any Internet user that is interested in accessing them. Web hosting makes use of the server/client model to distribute content. A Web hosting provider will provide its client right to access a Web server that will push client's content to recipients on request. Recipients use Web browsers like Microsoft Internet Explorer or Netscape Navigator to request content from the Web over their own Internet connection.

On a special computer Web sites are stored or hosted called as server. The server or host computer permits Internet users connected anywhere to reach site when they put host’s domain address in web browser. The server or host computers are set up so that when someone types Web address in browser, the address will follow a route from computer to computer until it reaches host computer and web site. After that Internet user will be able to browse throughout the Web site. Hosting companies usually need their own domain name in order to host with them.
Web hosts provide the technical resources and equipment that are required to offer a consumer with their own customized Web site. Hosting companies charge a fee for the storing Web site service and allowing Web site visitor traffic flow through computers to get information on site.

Web hosting services are more advantageous because the physical location of the Web server does not reside at the consumer's premises. Many small businesses take advantage of Web hosts in order to free themselves from pre occupying their scarce human and financial resources on Web host issues. Companies and individuals who outsource their Web presence to achieve the following objectives: improve own company focus, reduce operating costs, gain access to in-depth expertise, free internal resources for core competencies and obtain access to world-class capabilities to control IT functions which are difficult to handle. In multiple formats Web hosting is offered to the consumer based upon its requirements. These requirements are depend upon cost and infrastructure provided.

Types of Web Hosting

Web hosting services present in all sizes and shapes. It is useful to break down all services into several "classes" in order to understand the most fundamental differences in pricing and functionality. Each "class" speaks the needs of a particular type of customer.

1) Shared Hosting :
This is the most basic and important of all services. The hosting service providers put several web sites on a single powerful machine.

2) Virtual Dedicated Hosting :
This is a fairly new web hosting service, which seems to be bridge between "shared" and "dedicated" hosting. Several web sites are physically placed on a server, but the number of such sites is small in number and each one is given a dedicated "copy" of the operating system along with portion of computer resources, a copy of web server software in addition to direct "root-level" access to the server itself.

3) Dedicated Hosting:
Dedicated Hosting means that the computer which is used to serve web site is used by users only. Dedicated hosting allocates a Web site to its own server. This is more flexible because it has full control over the back end of the server including choice of OS.

4) Colocated Hosting (Colocation) :
Colocation provides ultimate degree of flexibility. This hosting consist of buying and installing own server on the web hosting provider's premises.

5) Managed hosting :
It is accompanied by a full suite of technical support, maintenance and monitoring services. In managed hosting, customers are provided with their own servers but are still responsible for virtually all administrative and maintenance duties.

Web Hosting Server Technologies :
The different hosting technologies are as follows:

1) Windows Hosting:
Windows hosting means hosting of web services that use Windows operating system. User should choose Windows hosting if he want to use Active Server Pages as server scripting or if he want to use a database like Microsoft Access or Microsoft SQL Server. Windows hosting is also the best choice if user want to develop web site using Microsoft Front Page.

2) Unix Hosting:
UNIX hosting means hosting of web services that uses UNIX operating system.
UNIX was the first reliable and stable web server operating system.

3) Linux Hosting:
Linux hosting means hosting of web services that uses Linux operating system.

4) ASP - Active Server Pages
Microsoft developed Active Server Pages as a server-side scripting technology.
With ASP dynamic web pages can be created by embedding scripting code inside HTML pages. The code is run by the web server before the page is returned to the browser. Both Visual Basic and JavaScript can be used for ASP code.

5) JSP
JSP is a server-side technology developed by Sun. With JSP dynamic web pages can be created by embedding Java code inside HTML pages. The code is run by the web server before the page is returned to the browser. Since JSP uses Java, the technology is not limited to any server-specific platform.

6) FrontPage
Microsoft developed FrontPage as web site design tool. FrontPage provides users easy way to develop a web site without any deep knowledge of web development. Most Windows hosting solutions maintain FrontPage server for users that use FrontPage to develop their web site.

7) PHP
PHP is a server-side scripting language which allows creating dynamic web pages by embedding script code inside HTML pages. The code is run by the web server before the page is returned to the browser.

8) Cold Fusion
Macromedia developed Cold Fusion, which is another server-side scripting language used to develop dynamic web pages.

Artificial Neural Network

2009-01-10T00:19:00.001+05:30

Artificial Neural Network (ANN)

Artificial neural networks are a method of information processing and computation that takes benefit of today's technology. Mimicking the processes present in biological neurons, artificial neural networks are used to predict and learn from a given set of data information. At data analysis neural networks are more robust than statistical methods because of their capability to handle small variations of parameters and noise.

An Artificial Neural Network is data information processing paradigm that is inspired by the way biological nervous systems such as the brain process information. The important element of this paradigm is the novel structure of the information processing system. It is created of a large number of highly interconnected processing elements known as neurons working in unison to solve specific problems. ANN is similar to people which learn by example. An ANN is defined for a specific application such as pattern recognition or data classification through a learning process. Learning in biological systems includes adjustments to the synaptic connections that exist between the neurons.

Why to use neural networks?
Either humans or other computer techniques use it to determine patterns and detect trends that are too complex to be noticed. In the category of information has been given to process, a trained neural network can be considered as an "expert".

It has following advantages:
a) Adaptive learning:
Capability to learn tasks based on the given data for training or initial experience.
b) Self-Organisation:
It can create its own organisation or representation of the information it receives during learning time.
c) Real Time Operation:
Its computations may be carried out in parallel and special hardware devices are being designed and manufactured which take advantage of this capability.
d) Fault Tolerance via Redundant Information Coding:
Partly destruction of a network leads to the corresponding degradation of performance. However some network capabilities may be retained even with major network damage.

Neural networks versus conventional computers
Neural networks have a different approach to problem solving than that of conventional computers. Conventional computers use an algorithmic approach in order to solve a problem. The problem cannot solve the problem until the specific steps that computer needs to follow are known. That limits the problem solving capability of conventional computers to problems that we already understand and know how to solve.

Neural networks and human brains process information in a similar way. The network is created from large number of highly interconnected processing elements working in parallel to solve a specific problem. Neural networks learn from example. They can’t be programmed to do a specific task.

Neural networks and conventional algorithmic computers are complements to each other. Neural networks tasks are more suited to an algorithmic approach like arithmetic operations. Large number of systems uses combination of the two approaches in order to perform at maximum efficiency.

Different architecture of neural networks
1) Feed-forward networks :
Feed-forward ANNs permit signals to transfer one way from input to output. There is no response i.e. the output of any layer doesn’t affect that same layer. Feed-forward ANNs tend to be straightforward networks that correlate inputs with outputs. They are widely used in pattern recognition. This type of organisation is called as bottom-up or top-down.

2) Feedback networks :
By using loops in the network, Feedback networks transfer signals in both directions. Feedback networks are powerful and complex. Feedback networks state is changing dynamically until they reach an equilibrium point. Until the input changes, they remain at the equilibrium point. Feedback architectures are called as interactive or recurrent.

3) Network layers:
Artificial neural network includes three layers of units: a layer of "input" units is connected to a layer of "hidden" units, which is connected to a layer of "output" units.

Input units:
The action of the input units represents the raw information that is fed into the network.

Hidden units:
The action of each hidden unit is determined by the activities of the input units and the weights on the connections between the input and the hidden units.

Output units:
The behaviour of the output units depends on the action of the hidden units and the weights between the hidden and output units.

4) Perceptrons

The most influential work on neural network went under the heading of 'perceptrons' a term coined by Frank Rosenblatt. The perceptron comes out to be an MCP model with some additional, fixed, preprocessing. Association units and their task are to remove specific, localized featured from the input images. Perceptrons mimic the basic idea behind the human visual system. They were used for pattern recognition even though their abilities extended a lot more.

Learning Process
The patterns and the subsequent response of the network can be divided into two general paradigms:
1) Associative mapping
In associated mapping the network learns to create a particular pattern on the set of input units whenever another particular pattern is applied on the set of input units. The associative mapping can be divided into two mechanisms:

1a) Auto-association:
An input pattern is related with itself and the states of input and output units coincide. This provides pattern completion to create a pattern whenever a portion of it or a distorted pattern is presented. In the second case, the network actually saves pairs of patterns building relationship between two sets of patterns.

1b) Hetero-association:
It is associated with two recall mechanisms:

Nearest-neighbor recall:
Where the output pattern created corresponds to the input pattern saved, which is closest to the pattern presented.

Interpolative recall:
Where the output pattern is a similarity-based interpolation of the patterns saved corresponding to the pattern presented.

2) Regularity detection
This unit corresponds to particular properties of the input patterns. Whereas in associative mapping the network saves the associations among patterns in regularity detection the response of each unit has a particular 'meaning'. This type of learning mechanism is vital for feature discovery and knowledge representation.

Every neural network has knowledge, which is contained in the values of the connections weights. Modifying the knowledge saved in the network as a function of experience means a learning rule for changing the values of the weights. Information is saved in the weight matrix of a neural network. Learning is the purpose of the weights. Learning is performed as follow; we can divide 2 types of neural networks:

i) Fixed networks
In which the weights remain the same. In such networks, the weights are fixed a priori regarding to the problem to solve.
ii) Adaptive networks
In which the weights do not remain same. For this network all learning methods can be classified into two major types:
Supervised learning
This incorporates an external teacher so that each output unit is told what its desired response to input signals ought to be. Global information may be required during the learning process. Paradigms of supervised learning consist error-correction learning, reinforcement learning and stochastic learning.

Unsupervised learning
It uses no external teacher and is dependent upon only local information. It is also called as self-organisation because it self-organizes data presented to the network and detects their emergent collective properties.

Transfer Function
Artificial Neural Network based on both the weights and the input-output function, which is specified for the units. This function typically falls into one of three types:
a) linear (or ramp)
b) threshold
c) sigmoid
For linear units the output action is proportional to the total weighted output.
For threshold units the output is set at one of two levels, based on whether the total input is greater than or less than some threshold value.
For sigmoid units the output varies rapidly but not linearly as the input changes. Sigmoid units allow a greater resemblance to real neurons than do linear or threshold units, but all three must be considered rough approximations.

To make a neural network that performs some specific work, we must choose how the units are interconnected to one another and we must set the weights on the connections appropriately. The connections decide whether it is possible for one unit to influence another. The weights define the strength of the influence.

Applications of neural networks

1) Detection of medical phenomena:
A variety of health based indices e.g., a combination of heart rate, levels of various substances in the blood, respiration rate can be observed. The onset of a particular medical condition could be related with a very complex mixing of changes on a subset of the variables being observed. Neural networks have been used to identify this predictive pattern so that the appropriate treatment can be specified.

2) Stock market prediction:
Fluctuations of stock prices and stock indices are complex, multidimensional deterministic phenomenon. Neural networks are used by many technical analysts to make decisions about stock prices dependent upon a large number of factors such as past performance of other stocks.

3) Credit assignment
For a loan a number of pieces of data information are usually known about an applicant. For instance, the applicant's age, education, occupation and many other data information may be present. After training a neural network on historical data, neural network analysis can determine the most relevant characteristics and use those to classify applicants as good or bad credit risks.

How to password protect MS word file?

2009-01-10T00:06:00.000+05:30

How to password protect MS word file?

Goto tools in MSword>option>security.

Then type desired password

Windows Driver Download

2009-01-10T00:04:00.001+05:30

:: Are u searching 4 any display driver or sound driver for your PC.

Just visit & find your driver from:-

www.driver32.com

Warning For You

2009-01-08T20:00:00.001+05:30

"WarN!nG" :

PaK!sTaN! (?) HacKerS TarGeT!nG 2 LaKhS oF !Nd!aN ComPuTeR NeTw0rK 2 Ru!N !t W!tH DowNl0aD!nG WeB V!ruSeS L!kE :

www.songs.pk

Tech Alrets For You

2009-01-08T19:58:00.001+05:30

TVs tout energy savings and Web; Windows 7 nears

Yahoo unveils partners for Web TV push

Sony to launch world's lightest 8-inch notebook PC

want free call world wide
Its simpal.

Try it

go register & download

m.eqo.com

& get 15min calling free wordwide.

Enjoy

:: Are u searching 4 any display driver or sound driver for your PC.
Just visit & find your driver from:-

www.driver32.com

Want To find Out When Your Email Has Been Read By The Recipient!

2008-12-23T00:49:00.004+05:30

Want To Know Is Your Sent Mail Read or Not ..

Then dont worry try out dis,

Goto : www.spypig.com

Then

Copy And Paste this image & send to mail or chat friend ..

When They Open it ,

This Site Inform You There Status & IP..

~~ Cheers ~~

Improve Startup Speed

2008-12-23T00:34:00.002+05:30

To Improve Your System Start Up Speed ..
Follow the below

Press and Hold Shift key while windows is being loaded..

Do de above,,Before Desktop Comes

Then other programs will not start..

Now You can see the better speed..

~~CHEERS~~

Opertate PC WithOut Mouse

2008-12-17T12:34:00.002+05:30

Want To Operate PC Without Mouse ???

Cool Try Out This

Press

Shift + Alt + NumLock

Then use Number Keys To Operate Mouse !!!!

Tips To Professional Internet Users

2008-12-17T11:07:00.002+05:30

If You are Professional User Of Internet & Password Security is most.

This Useful Tips For you.

-->Use Symbol & Alpha Numeric Password.

-->Create Minimum 8 Characters Password In Any Account.

-->Use Upper And Lower Case Characters In Your Password.

-->Don't Use Your Name In Password.

What is the difference between Cc and Bcc?

2008-12-13T11:13:00.001+05:30

In Email,

Cc stands for carbon copy which means that whose address appears after the Cc: header would receive a copy of the message. Also, the Cc header would also appear inside the header of the received message.

Bcc stands for blind carbon copy which is similar to that of Cc except that the Email address of the recipients specified in this field do not appear in the received message header and the recipients in the To or Cc fields will not know that a copy sent to these address.

Past Pages Of Any Site

2008-12-10T23:57:00.002+05:30

Want to see the past pages of any website in any date?

www.archive.org

here u can browse any website by any date !!!

Tips To Play DVD files in Windows Media Player 10

2008-12-10T23:51:00.003+05:30

A Powerfull Hidden trick for play DVD in Windows Media Player 10 series..

Open Run

=>type

dvdplay

then press enter...

Flash && Animation

2008-12-06T21:30:00.006+05:30

Best Flash Bookmarks:

www.flashvista.com

www.flashgoddess.com

www.internetcross.com

www.globz.com

www.yamago.net

Best Sits For Graphics And Animation :

www.psdtuts.com

www.aiburn.com

www.dezignus.com

www.smashingmagzine.com

Lot Of Tutorial Here....
Try IT

Unknown Tech Info For U

2008-12-06T21:13:00.002+05:30

Want U See ur System Hardware Infomartion Try this Shortcut "Windows Key +' Pause/Break '".

Here a Simple Trick For View & Edit Your PC Setting Quickly

Goto Run
type "wscui.cpl"

Hidden Trick For open UR Firwall Setting

Goto Run
type"firewall.cpl"

With this trick You can change Everything In Firewall

GTalk not loading Winamp && Media PlayerSongs

2008-12-02T20:14:00.002+05:30

Google Talk is crashing when I share my music status with Winamp 5.5

If your Google Talk client crashes when you share your music status with Winamp 5.5, please follow the steps below to resolve the issue:
Exit Google Talk and Winamp.

Click start on your Windows taskbar.
Select Run and enter: [ type nul: >>"%programfiles%\winamp\winamp.m3u" ]Make sure you use two carets (>>), not one (>).
Click OK.
Note: If you installed Winamp in a different location from the default one, you'll need to use that location in the command in step 3. Replace %programfiles% with the correct location.

Why isn't my music status showing when I use Windows Media Player?

If Windows Media Player or your Windows desktop crashes, Windows Media Player will disable all plug-ins, including the music-status plug-in for Google Talk. To re-enable the Google Talk plug-in, follow these steps:

Open Windows Media Player.
From the View menu, select Plug-ins > Options...
From the Category section of the Plug-ins tab, select Background.
Select the Google Talk Music Plugin checkbox.
Click OK.
You'll need to close and restart Windows Media Player for the change to take effect.
A note for Vista users: If you can't find the Google Talk Music plug-in in the Plug-ins tab of your Windows Media Player settings, try these steps:
Uninstall Google Talk.
Visit http://www.google.com/talk/
Click Download Google Talk client near the bottom of the page.
Save the installation file to your desktop.
Right-click the installation file (googletalk-setup.exe) on your desktop and select Run as administrator.
Follow the instructions to install Talk.

ராஜேஷ்

Want To Uninstall the software

2008-12-02T00:53:00.005+05:30

THIS SOFTWARE USEFUL TO 100% UNINSTALL ANY SOFTWARE...

Revo Uninstaller is a software that lets you completely uninstall programs and it's easier to use than the built-in "Add or remove programs". You can search for a program or locate it in a more intuitive way: enter in the Hunter Mode, open the program you want to uninstall and drag the target to your program's window.

After finding the program, Revo Uninstaller analyzes the program's data, launches the uninstaller and shows you a list of leftovers (files, folders, registry entries related to the application). The application does a pretty good job at identifying them, but you should still check the results before selecting everything. "Even if you have a broken installation, Revo Uninstaller scans for an application's data on your hard disk drives and in the Windows registry and shows all found files, folders and registry items so you can delete them."

thats it
njoy...

GRE Complete Material

2008-11-22T11:32:00.001+05:30

http://rapidshare.com/files/141140953/Rea_Gre_Tests.rar

http://rapidshare.com/files/141140365/Pwrprep.rar

http://rapidshare.com/files/140893044/bigbook.zip

http://rapidshare.com/files/140894025/ARCO.rar

http://rapidshare.com/files/141141384/Pwrprep2.rar
http://rapidshare.com/files/141142627/cambridge.rar
http://rapidshare.com/files/141144108/gre_materials.rar
Barrons_CD.rar

http://rapidshare.com/files/141148721/Barrons_CD.rar
Kaplan_CD.rar

http://rapidshare.com/files/141158781/Kaplan_CD.rar
Word_Command.rar

http://rapidshare.com/files/141160465/Word_Command.rar

NOVA

http://rapidshare.com/files/146339399/Nova.rar

Want to change Windows Start Button

2008-11-22T11:28:00.002+05:30

This Document Contain Easy Information To change ur windows Start Button Text

http://rapidshare.com/files/166176749/windows_start_button_text.doc.html

Kaspersky Anti-Virus 2009 - 8.0.0.454

2008-11-18T15:03:00.002+05:30

Latest Version

* System watch. System watcher (all-in-one system for registering

events).
- HIPS (host intrusion prevention system - proactive defense, which

is based on limiting application actions on a system)
- PDM (system of proactive defense, which is based on application

behavior analysis for malicious/suspicious activities)
- Firewall (personal protection screen)
* Malware protection
- Protection of files and memory (File-Antivirus)
- Protection of email and IM (Mail-Antivirus)
- Protection of WEB (Web-Antivirus)
* Online Security
- Protection from Phishing (Anti-Phishing)
- Protection against network attacks (IDS)
- Protection from auto-dialers (Anti-Dialer)
* Content Filtering
- Spam Filtering (Anti-Spam)
- Banner Filtering (Anti-Banner)
- Parental Control
* On Demand Scanning (Scan tasks)
* Updater

No Password, Don't Forget to say Thanks!

http://kewlshare.com/dl/4d86d363a3e9/Kaspersky_Anti-Virus_2009_8.0.0.
454__PC7_M107.rar.html

More than 100,000 Universal Windows Drivers

2008-11-18T14:49:00.001+05:30

All kind of driver old-latest up to date
Size : 530 MB

Just pop the Universal Driver CD in and Windows will automatically search the comprehensive drivers. This CD, (Iso format) contains software drivers for over 100,000 hardware components from brands such as Dell, HP, Compaq, IBM, Sony, Toshiba, Panasonic, as well as hardware component manufacturers Intel, 3Com, VIA, nVidia, ATI, SoundMax, and many more!

http://rapidshare.com/files/161872806/100000.Universal.Driver.08.2008.part01.rar
http://rapidshare.com/files/161873014/100000.Universal.Driver.08.2008.part02.rar
http://rapidshare.com/files/161872799/100000.Universal.Driver.08.2008.part03.rar
http://rapidshare.com/files/161872908/100000.Universal.Driver.08.2008.part04.rar
http://rapidshare.com/files/161872954/100000.Universal.Driver.08.2008.part05.rar
http://rapidshare.com/files/161869308/100000.Universal.Driver.08.2008.part06.rar

Rapidshare Tools Collection

2008-11-18T14:47:00.000+05:30

Latest Rapidshare Tools Collection : :

* 28.000 Proxies List
* BC-Leecha v2.42
* Link Grabber v3.0.2
* Proxy Finder v1.1
* Rapid Check v0.4
* Rapid Harvest v1.2.0.5
* Rapid Leecher v4.5 Beta
* Rapid Search Beta v0.2
* RapidShare - the way YOU like it!
* RapidShare DeCoder v0.2
* Rapidshare Free Account Notifier v1.0
* Rapidshare Grabber v1.4.4a

Rapidshare Instant Downloader v1.3.3
Rapidshare Premium Account Generator v1.0
Rapidshare Source Code
Rapidshare Downloader Live
RapidUp v1.3
RapidUp (latest version)
Rapishare Bypasser
Rapishare premium Grabber
Rapishare collect script
Rapishare siggy

Links to download :

http://rapidshare.com/files/132680672/AIO_30_Best_Rapidshare_Tools_CollectionBy_Rexy.part1.rar

http://rapidshare.com/files/132681778/AIO_30_Best_Rapidshare_Tools_CollectionBy_Rexy.part2.rar

Rapidshare Premium Links

2008-11-17T00:36:00.000+05:30

Rapidshare Premium Links : :

http://yourrapidsolution.com/rapid/index.php
http://vip.hotspotwarez.com/rs/index.php
http://www.rstiger.com/download.php
http://wautersjoris.deds.nl/
http://www.hlusoe.info/
http://www.promonkey.net/rapid/

Create a bootable USB drive!

2008-11-14T21:56:00.003+05:30

Descrption:
I had to search all over for this information, so I stole a little here, borrowed a little there, and made up what I couldn't find, to get it all in one place.
Hopefully, this will save everyone some time.

First, this is PE version 2.0, and earlier versions will not work. I do not/will not work with BartPE, so I haven't a clue what needs to be done in that environment.

Your USB and the port it is using must be USB 2.0. I don't know if USB 1.0 will work slowly, or not at all.

I'm assuming you've created a bootable PE Version 2.0 CD.
I used the drive letters that my computer assigned to the devices. Yours may be different.
C:=local hard drive
D:=CD/DVD drive
E:=USB Thumb drive
X:=PE's RAM disk

You need to assure that you select the proper disks, as you will be erasing and formatting the thumb drive. I will not be responsible for any data loss or woes you encounter!

You'll need MagicISO, to extract all folders and files (including hidden files) from your CD to a file on your C: drive (I used c:\bootusb)
(You probably already have these files in a folder, somewhere. you needed to use them to create the ISO. If not, extract them before you boot the PE CD).

Boot your PE version 2.0 CD
type these commands:
disk part
select disk 1 (this was my USB drive. type in "detail disk" to be sure you've selected the USB drive)
clean (you are erasing the selected disk. I hope you got it right!)
create partition primary
select partition 1
active
format fs=fat32 (this takes a while)
assign
exit

You're now back at the command prompt, and need to copy the files from the folder you created on your hard drive to the USB drive.
xcopy c:\bootusb\*.* e: /h /e (this also takes a while)

You can't copy the files from the RAM drive, as they're in use by PE
I don't think (but haven't tried) you can copy them from the CD, as they're compressed. (

Good luck, and I hope to have saved someone a bit of trouble figuring this out.

Change the Logon Background Colour

2008-11-14T21:56:00.001+05:30

Change the Logon Background Colour:-

1.Use a registry editing tool to navigate to the following tool:

HKEY_USERS\.DEFAULT\Control Panel\Colors\Background

2. Change the following value:-
Data Type: REG_SZ
Value Name: Background
Value: Decimal RGB value for the colour you wish to set, for example:

Red: 255 0 0
Green: 0 255 0
Blue: 0 0 255
Black: 0 0 0
White: 255 255 255

Intel Atom

2008-11-09T17:43:00.003+05:30

Introduction

For a few months, we’d been hearing talk of a new dedicated Intel processor for MIDs (Mobile InternetDevices), intended to compete with ARM processors. Initially known by the names Silverthorne and Diamondville, the processors in this new line will be called "Atom". These chips have a few surprises in store.

Interesting and Surprising Choices
Atom CPUs are surprising for more than one reason: they have modern functions (EM64T, SSSE3, etc.) grafted onto an older architecture The Atom is the first in-order x86 since the Pentium. Power management and fabrication costs are the two imperatives Intel seems to have been guided by, at the expense (with no attempt made to hide it) of performance. So, no, don’t expect a competitor to Core 2 Duo. But what does the Atom really have to offer? We’ll see that as this piece unfolds.

Intel versus AMD Processor

2008-11-07T15:14:00.001+05:30

This evaluation of current desktop processors utilises over 60 benchmark tests including office and multimedia software, 3D games, Internet applications, video rendering and compression. We have used benchmarks that are relevant to a range of market sectors in order to get a balanced view of CPU performance. However, in an ideal world, you should also run your own mission-critical applications on any processor that you're considering.

Of course, performance is only one aspect of a processor purchase decision. For example, the Athlon 64's support for the NX (No Execute) feature safeguards it from certain virus attacks, and could be reason enough to choose an AMD processor. And if you're after a quiet PC, then AMD's chips have clear advantages over Intel's latest 'Prescott' Pentium 4. The power consumption of the Athlon 64 is lower than that of the Pentium 4 thanks to AMD's use of Silicon-on-Insulator (SOI) technology. The Athlon's 64's 64-bit capability is also a potential advantage, although this feature remains largely unused because of the missing operating system support -- 64-bit Windows XP has now been delayed until 2005.

System	Idle	Max

Athlon 64 3800+ (Nforce 3)	91W	172W
Athlon 64 3800+ (KT800 Pro)	82W	162W
Pentium 4 560 (925X)	155W	258W

AMD Phenom X4 9000 Series

2008-11-07T15:09:00.001+05:30

INCREDIBLE PERFORMANCE

The ultimate megatasking experience. Featuring true multi-core design and award-winning AMD64 technology with Direct Connect Architecture, AMD Phenom™ processors deliver the ultimate megatasking experience by providing direct and rapid information flow between processor cores, main memory, and graphics and video accelerators. AMD Phenom™ processors have the technology to break through the most challenging processing loads. AMD Phenom™ processors feature low latency access to main memory for amazingly rapid response and phenomenal system performance. AMD Phenom™ processors were designed for megatasking—running multiple, multi-threaded applications. Surge through the most demanding processing loads, including advanced multitasking, critical business productivity, advanced visual design and modeling, serious gaming, and visually stunning digital media and entertainment.

Phenomenal performance with advanced processor design. The AMD Phenom™ processors are the most advanced processors for true multitasking with true quad-core design. Don’t get bogged down by non-native quad-core processors and obsolete front side bus architectures. With an integrated memory controller and shared L3 cache, AMD Phenom™ processors have low-latency access to main memory for amazingly rapid system response and phenomenal system performance.

Blast through performance bottlenecks. All AMD Phenom™ processors feature AMD64 with Direct Connect Architecture to blast through performance bottlenecks. Award winning HyperTransport™ 3.0 technology just got faster, providing support for full 1080p high-definition video and extreme total system bandwidth.

Shatter the memory barrier. Superior AMD64 architecture offers direct access to DDR2 memory. Enjoy virtually unlimited memory options with AMD64 technology and 64-bit Windows Vista.® Shatter the memory barrier with AMD Phenom™ processors and 64-bit Windows Vista.®

INTENSELY VISUAL

Experience Windows Vista.® Harness the power of Windows Vista® with the AMD Phenom™ processors. AMD Phenom™ processors divide and conquer the most complex tasks with true multi-core design. Enjoy the ultimate megatasking experience on Windows Vista.® Enjoy virtually unlimited memory options with AMD64 technology and 64-bit Windows Vista.® Shatter the memory barrier with AMD Phenom™ processors and Windows Vista.®

STRIKINGLY EFFICIENT

Strikingly efficient Cool‘n’Quiet™ 2.0 technology.With the next generation of award-winning Cool‘n’Quiet™ technology, Cool‘n’Quiet™ 2.0 technology reduces heat and noise so you can experience amazing performance without distraction. Combined with core enhancements that can improve overall power savings, AMD Phenom™ processors deliver seamless multitasking and optimum energy efficiency. Work, play, talk, and share a PC that’s seen, not heard.

Purchase with Confidence
Founded in 1969, AMD has shipped more than 240 million PC processors worldwide. Customers can depend on AMD64 processors and AMD for compatibility and reliability. AMD processors undergo extensive testing to help ensure compatibility with Microsoft Windows XP, Vista, Windows NT®, Windows 2000, as well as Linux and other PC operating systems. AMD works collaboratively with Microsoft and other ecosystem partners to achieve compatibility of AMD processors and to expand the capability of software and hardware products leveraging AMD64 technology. AMD conducts rigorous research, development, and validation to help ensure the continued integrity and performance of its products.

Intel Entry Storage System

2008-11-07T15:06:00.001+05:30

Easy-to-use Network Attached Storage (NAS) solution adds capacity, data protection and central access for small businesses, and the Small Office and Home Office (SOHO).

The Intel® Entry Storage System SS4200-E is a complete yet flexible hardware and software NAS solution that instantly adds storage capacity to small business, and the small office and home office. Powered by software from EMC, the worldwide leader in information management, the Intel Entry Storage System SS4200-E offers an intuitive user interface and easy 4-step setup process. Out-of-the-box RAID and Retrospect* backup software together deliver the necessary security to protect irreplaceable digital data such as accounting records, financial data, customer information, email, sales records, product info, databases—everything a small business relies on to keep their business running. With four USB 2.0 ports and two SATA ports, the Intel Entry Storage System SS4200-E can be connected to most digital devices as well as additional storage devices to form the core of a shared, centralized data access system.

The Intel Entry Storage System SS4200-E was designed specifically for the small business with flexibility and growth in mind, allowing you to customize and differentiate your solutions.

Economical servers for small business and clusters

2008-11-07T15:05:00.001+05:30

Intel® Xeon® Processor 3000 Sequence :

The Intel® Xeon® processor 3000 sequence-based platforms unleash the computing power of Intel Xeon processors. The new 45 nm Quad and Dual-Core processors feature enhanced Intel® Core™ microarchitecture that provides your business with exceptional performance and power efficiency at a very affordable cost.

These servers are ideal for small business owners looking for ways to grow business, manage operation more effectively and efficiently, and protect and secure one of their most important assets - information.

Intel® Xeon® Processor 7000 Sequence

2008-11-07T15:02:00.000+05:30

The Intel® Xeon® processor 7400 series, offers the industry's highest virtualization performance so you can do more with less. With key platform innovations built-in, the Intel Xeon processor 7400 series offers more headroom, reliability, and the highest expandability for large-scale server consolidation.

Best-in-class performance ::

With enhanced 45nm Intel® Core™ microarchitecture, the new Intel Xeon processor 7400 series is best-in-class for demanding enterprise workloads with almost 50% better performance in some cases and up to 10% reduction in platform power compared to previous generation expandable servers.¹ Designed and optimized for IT, these 6-core processors provide industry-leading multi-core processing and greater computing performance without increasing footprint and power demands.

With 16MB shared L3 cache, scalability beyond 4 sockets, 1066 million transfers per second (MT/s), and support for up to 256GB of RAM, the Intel Xeon processor 7400 series is the ideal choice for your data-intensive, business-critical performance requirements.

Headroom and scalability built in ::

Offering more low voltage options including 65W 6-core and 50W 4-core processors, Intel Xeon processor 7400 series for blade and ultra-dense platforms reduce cooling requirements, lowering IT costs. In addition, these processors are designed with Intel® Virtualization Technology (Intel® VT), enabling an ecosystem of software-based virtualization from industry leading software providers.

DBMS(Data base management system)

2008-11-05T11:46:00.002+05:30

DBMS(Data base management system)

1) In what kind of storage structure for strings, one can easily insert, delete, concatenate and rearrange substrings?

a)fixed length storage structure b) variable length storage with fixed maximum
c)linked list storage d) array type storage

2) What is the time required to search an element in a linked list of length n?

a) O(log2 n) b) O(n) c) O(1) d) O(n2)

1) Consider a linked list of n element which is pointed by an external pointer. What is the time taken to delete the element which is successor of the element pointed to by a given pointer

a) O(1) b) O(log2 n) c) O(n) d) O(n log2 n)

2) Consider a linked list of n elements. What is the time taker to insert an element after an element pointed by some pointer?

a) O(1) b) O(log2 n) c) O(n) d) O(n log2 n)

3) Consider an undirected graph G with n vertices and e edges. Whjat is the time taken by Depth First Search (DFS) if the graph is represented by (i) adjacency matrix, (ii) adjacency list?

a) O(n2), O(n) b) O(n2), O(e) c) O(e), O(n2) d) O(e+n), O(e)

4) An undirected graph G with n vertices and e edges is represented by adjacency list. What is the time required to generate all the connected components?

a) O(n) b) O(e) c) O(e + n) d) O(e2)

5) Which of the following statements is false?

a) every tree is a bipartite graph b) a tree contains a cycle
c) a tree with n.nodes contains n-1 edges d) a tree is a connected graph

6) A graph G with n nodes is bipartite if it contains

a) n edges b) a cycle of odd length c) no cycle of odd length d) n2 edges

7) In what tree, for every node the height of its left subtree and right subtree differ at least by one

a) binary search tree b) AVL – tree c) Complete tree d) Threaded binary tree

8) A complete binary tree with the property that the value at each node is at least as large as the values at its children is known as

a) binary search tree b) AVL tree c) completely balanced tree d) Heap

9) A full binary tree with n leaves contains

a) n nodes b) log2 n nodes c) 2n-1 nodes d) 2n nodes

10) A full binary tree with n non-leaf nodes contains

a) log2 n nodes b) n + 1 nodes c) 2 n nodes d) 2 n + 1 nodes

11) Preorder is nothing but

a) depth first order b)breadthfirstorder c) topological order d) linear order

12) What traversal techniques lists the notes of a binary search tree is ascending order?

a) post order b) inorder c) preorder d) none of the above

13) Consider a sorted binary insertion tree. What must be done to produce a sorted array of numbers (for printing) from the sorted binary insertion tree?

a) preoder traversal b)postorder traversal c) inorder traversal d) top-down traversal

14) The concatenation of two lists is to be performed in O(1) time. Which of the following implementations of a list should be used?

a) singly linked list b) doubly linked list
c) circular doubly linked list d) array implementation

15) Which of the follwing algorithm solves the all pairs shortest path problem

a) Greedy b) Depth-First search
c) Dyanamic programming d) Divide &Conquer

16) Which of the follwing algorithm solves the Quick Sort problem

a) Greedy b) Depth-First search
c) Dyanamic programming d) Divide &Conquer

17) Which of the follwing algorithm solves the Minimum weight spanning tree problem

a) Greedy b) Depth-First search
c) Dynamic programming d)Divide&Conquer

20) Which of the following algorithm solves the Connected components problem

a) Greedy b) Depth-First search
c) Dynamic programming d)Divide&Conquer

21) selection sort’s worst case Space complexity is …

a) 0 b) O(n) c) O(logn) d)None

22) Bubble sort ‘s worst case Space complexity is…

a) 0 b) O(n) c) O(logn) d)None

23) Insertion sort’s worstcase Space complexity is….

a) 0 b) O(n) c) O(logn) d)None

24) Merge sort’s worst case Space complexity is…

a) 0 b) O(n) c) O(logn) d)None.

25) Quick sort’s worstcase Space complexity is….

a) 0 b) O(n)
c) O(logn) d)None

26)selection sort’s average case Space complexity is …

a) 0 b) O(n)
c) O(logn) d)None

27)Bubble sort ‘s average case Space complexity is….

a) 0 b) O(n)
c) O(logn) d)None

28) Insertion sort’s average case Space complexity is….

a) 0 b) O(n)
c) O(logn) d)None

29) Merge sort’s average case Space complexity is…

a) 0 b) O(n)
c) O(logn) d)None.

30) Quick sort’s average case Space complexity is….

a) 0 b) O(n)
c) O(logn) d)None

Answers
1) C 2) B 3) A 4) A 5) B
6) C 7) B 8) C 9) B 10) D
11) C 12) D 13) A 14) B 15) A
16) D 17) B 18) D 19) C 20) B
21) A 22) A 23) A 24) B 25) B
26) A 27) A 28) A 29) B 30) B

Aptitude Questions

2008-11-05T11:37:00.000+05:30

Microsoft Word - TOEFL.doc

Aptitude Questions

1.If 2x-y=4 then 6x-3y=?

(a)15
(b)12
(c)18
(d)10

Ans. (b)

2.If x=y=2z and xyz=256 then what is the value of x?

(a)12
(b)8
(c)16
(d)6

Ans. (b)

3. (1/10)¹⁸ - (1/10)²⁰= ?

(a) 99/10²⁰(b) 99/10
(c) 0.9
(d) none of these

Ans. (a)

4.Pipe A can fill in 20 minutes and Pipe B in 30 mins and Pipe C can empty the same in 40 mins.If all of them work together, find the time taken to fill the tank

(a) 17 1/7 mins
(b) 20 mins
(c) 8 mins
(d) none of these

Ans. (a)

5. Thirty men take 20 days to complete a job working 9 hours a day.How many hour a day should 40 men work to complete the job?

(a) 8 hrs
(b) 7 1/2 hrs
(c) 7 hrs
(d) 9 hrs

Ans. (b)

6. Find the smallest number in a GP whose sum is 38 and product 1728

(a) 12
(b) 20
(c) 8
(d) none of these

Ans. (c)

7. A boat travels 20 kms upstream in 6 hrs and 18 kms downstream in 4 hrs.Find the speed of the boat in still water and the speed of the water current?

(a) 1/2 kmph
(b) 7/12 kmph
(c) 5 kmph
(d) none of these

Ans. (b)

8. A goat is tied to one corner of a square plot of side 12m by a rope 7m long.Find the area it can graze?

(a) 38.5 sq.m
(b) 155 sq.m
(c) 144 sq.m
(d) 19.25 sq.m

Ans. (a)

9. Mr. Shah decided to walk down the escalator of a tube station. He found that if he walks down 26 steps, he requires 30 seconds to reach the bottom. However, if he steps down 34 stairs he would only require 18 seconds to get to the bottom. If the time is measured from the moment the top step begins to descend to the time he steps off the last step at the bottom, find out the height of the stair way in steps?

Ans.46 steps.

10. The average age of 10 members of a committee is the same as it was 4 years ago, because an old member has been replaced by a young member. Find how much younger is the new member ?

Ans.40 years.

11. Three containers A, B and C have volumes a, b, and c respectively; and container A is full of water while the other two are empty. If from container A water is poured into container B which becomes 1/3 full, and into container C which becomes 1/2 full, how much water is left in container A?

12. ABCE is an isosceles trapezoid and ACDE is a rectangle. AB = 10 and EC = 20. What is the length of AE?

Ans. AE = 10.

13. In the given figure, PA and PB are tangents to the circle at A and B respectively and the chord BC is parallel to tangent PA. If AC = 6 cm, and length of the tangent AP is 9 cm, then what is the length of the chord BC?

Ans. BC = 4 cm.

15 Three cards are drawn at random from an ordinary pack of cards. Find the probability that they will consist of a king, a queen and an ace.

Ans. 64/2210.

16. A number of cats got together and decided to kill between them 999919 mice. Every cat killed an equal number of mice. Each cat killed more mice than there were cats. How many cats do you think there were ?

Ans. 991.

17. If Log2 x - 5 Log x + 6 = 0, then what would the value / values of x be?

Ans. x = e2 or e3.

18. The square of a two digit number is divided by half the number. After 36 is added to the quotient, this sum is then divided by 2. The digits of the resulting number are the same as those in the original number, but they are in reverse order. The ten's place of the original number is equal to twice the difference between its digits. What is the number?

Ans. 46

19.Can you tender a one rupee note in such a manner that there shall be total 50 coins but none of them would be 2 paise coins.?

Ans. 45 one paisa coins, 2 five paise coins, 2 ten paise coins, and 1 twenty-five paise coins.

20.A monkey starts climbing up a tree 20ft. tall. Each hour, it hops 3ft. and slips back 2ft. How much time would it take the monkey to reach the top?

Ans.18 hours.

21. What is the missing number in this series? 8 2 14 6 11 ? 14 6 18 12

Ans. 9

22. A certain type of mixture is prepared by mixing brand A at Rs.9 a kg. with brand B at Rs.4 a kg. If the mixture is worth Rs.7 a kg., how many kgs. of brand A are needed to make 40kgs. of the mixture?

Ans. Brand A needed is 24kgs.

23. A wizard named Nepo says "I am only three times my son's age. My father is 40 years more than twice my age. Together the three of us are a mere 1240 years old." How old is Nepo?

Ans. 360 years old.

24. One dog tells the other that there are two dogs in front of me. The other one also shouts that he too had two behind him. How many are they?

Ans. Three.

25. A man ate 100 bananas in five days, each day eating 6 more than the previous day. How many bananas did he eat on the first day?

Ans. Eight.

26. If it takes five minutes to boil one egg, how long will it take to boil four eggs?

Ans. Five minutes.

27. The minute hand of a clock overtakes the hour hand at intervals of 64 minutes of correct time. How much a day does the clock gain or lose?

Ans. 32 8/11 minutes.

28. Solve for x and y: 1/x - 1/y = 1/3, 1/x2 + 1/y2 = 5/9.

Ans. x = 3/2 or -3 and y = 3 or -3/2.

29. Daal is now being sold at Rs. 20 a kg. During last month its rate was Rs. 16 per kg. By how much percent should a family reduce its consumption so as to keep the expenditure fixed?

Ans. 20 %.

30. Find the least value of 3x + 4y if x2y3 = 6.

Ans. 10.

31. Can you find out what day of the week was January 12, 1979?

Ans. Friday.

32. A garrison of 3300 men has provisions for 32 days, when given at a rate of 850 grams per head. At the end of 7 days a reinforcement arrives and it was found that now the provisions will last 8 days less, when given at the rate of 825 grams per head. How, many more men can it feed?

Ans. 1700 men.

33. From 5 different green balls, four different blue balls and three different red balls, how many combinations of balls can be chosen taking at least one green and one blue ball?

Ans. 3720.

34. Three pipes, A, B, & C are attached to a tank. A & B can fill it in 20 & 30 minutes respectively while C can empty it in 15 minutes. If A, B & C are kept open successively for 1 minute each, how soon will the tank be filled?

Ans. 167 minutes.

35. A person walking 5/6 of his usual rate is 40 minutes late. What is his usual time? Ans. 3 hours 20 minutes.

36.For a motorist there are three ways going from City A to City C. By way of bridge the distance is 20 miles and toll is $0.75. A tunnel between the two cities is a distance of 10 miles and toll is $1.00 for the vehicle and driver and $0.10 for each passenger. A two-lane highway without toll goes east for 30 miles to city B and then 20 miles in a northwest direction to City C.

1. Which is the shortest route from B to C

(a) Directly on toll free highway to City C
(b) The bridge
(c) The Tunnel
(d) The bridge or the tunnel
(e) The bridge only if traffic is heavy on the toll free highway

Ans. (a)

2. The most economical way of going from City A to City B, in terms of toll and distance is to use the

(a) tunnel
(b) bridge
(c) bridge or tunnel
(d) toll free highway
(e) bridge and highway

Ans. (a)

3. Jim usually drives alone from City C to City A every working day. His firm deducts a percentage of employee pay for lateness. Which factor would most influence his choice of the bridge or the tunnel ?

(a) Whether his wife goes with him
(b) scenic beauty on the route
(c) Traffic conditions on the road, bridge and tunnel
(d) saving $0.25 in tolls
(e) price of gasoline consumed in covering additional 10 miles on the bridge

Ans. (a)

4. In choosing between the use of the bridge and the tunnel the chief factor(s) would be:
I. Traffic and road conditions
II. Number of passengers in the car
III. Location of one's homes in the center or outskirts of one of the cities
IV. Desire to save $0.25

(a) I only
(b) II only
(c) II and III only
(d) III and IV only
(e) I and II only

Ans. (a)

37.The letters A, B, C, D, E, F and G, not necessarily in that order, stand for seven consecutive integers from 1 to 10
D is 3 less than A
B is the middle term
F is as much less than B as C is greater than D
G is greater than F

1. The fifth integer is
(a) A
(b) C
(c) D
(d) E
(e) F

Ans. (a)

2. A is as much greater than F as which integer is less than G
(a) A
(b) B
(c) C
(d) D
(e) E

Ans. (a)

3. If A = 7, the sum of E and G is
(a) 8
(b) 10
(c) 12
(d) 14
(e) 16

Ans. (a)

4. A - F = ?
(a) 1
(b) 2
(c) 3
(d) 4
(e) Cannot be determined

Ans. (a)

5. An integer T is as much greater than C as C is greater than E. T can be written as A + E. What is D?
(a) 2
(b) 3
(c) 4
(d) 5
(e) Cannot be determined

Ans. (a)

6. The greatest possible value of C is how much greater than the smallest possible value of D?
(a) 2
(b) 3
(c) 4
(d) 5
(e) 6

Ans. (a)

38.
1. All G's are H's
2. All G's are J's or K's
3. All J's and K's are G's
4. All L's are K's
5. All N's are M's
6. No M's are G's

1. If no P's are K's, which of the following must be true?

(a) All P's are J's
(b) No P is a G
(c) No P is an H
(d) If any P is an H it is a G
(e) If any P is a G it is a J

Ans. (a)

2. Which of the following can be logically deduced from the conditions stated?

(a) No M's are H's
(b) No M's that are not N's are H's
(c) No H's are M's
(d) Some M's are H's
(e) All M's are H's

Ans. (a)

3. Which of the following is inconsistent with one or more of the conditions?

(a) All H's are G's
(b) All H's that are not G's are M's
(c) Some H's are both M's and G's
(d) No M's are H's
(e) All M's are H's

Ans. (a)

4. The statement "No L's are J's" is
I. Logically deducible from the conditions stated
II. Consistent with but not deducible from the conditions stated
III. Deducible from the stated conditions together with the additional statement "No J's are K's"

(a) I only
(b) II only
(c) III only
(d) II and III only
(e) Neither I, II nor III

Ans. (a)

39.In country X, democratic, conservative and justice parties have fought three civil wars in twenty years. TO restore stability an agreement is reached to rotate the top offices President, Prime Minister and Army Chief among the parties so that each party controls one and only one office at all times. The three top office holders must each have two deputies, one from each of the other parties. Each deputy must choose a staff composed of equally members of his or her chiefs party and member of the third party.

1. When Justice party holds one of the top offices, which of the following cannot be true

(a) Some of the staff members within that office are justice party members
(b) Some of the staff members within that office are democratic party members
(c) Two of the deputies within the other offices are justice party members
(d) Two of the deputies within the other offices are conservative party members
(e) Some of the staff members within the other offices are justice party members.

Ans. (a)

2. When the democratic party holds presidency, the staff of the prime minister's deputies are composed
I. One-fourth of democratic party members
II. One-half of justice party members and one-fourth of conservative party members
III. One-half of conservative party members and one-fourth of justice party members.

(a) I only
(b) I and II only
(c) II or III but not both
(d) I and II or I and III
(e) None of these

Ans. (a)

3. Which of the following is allowable under the rules as stated:

(a) More than half of the staff within a given office belonging to a single party
(b) Half of the staff within a given office belonging to a single party
(c) Any person having a member of the same party as his or her immediate superior
(d) Half the total number of staff members in all three offices belonging to a single party
(e) Half the staff members in a given office belonging to parties different from the party of the top office holder in that office.

Ans. (a)

4. The office of the Army Chief passes from Conservative to Justice party. Which of the following must be fired.

(a) The democratic deputy and all staff members belonging to Justice party
(b) Justice party deputy and all his or hers staff members
(c) Justice party deputy and half of his Conservative staff members in the chief of staff office
(d) The Conservative deputy and all of his or her staff members belonging to Conservative party
(e) No deputies and all staff members belonging to conservative parties.

Ans. (a)

40.In recommendations to the board of trustees a tuition increase of $500 per year, the president of the university said "There were no student demonstrations over the previous increases of $300 last year and $200 the year before". If the president's statement is accurate then which of the following can be validly inferred from the information given:
I. Most students in previous years felt that the increases were justified because of increased operating costs.
II. Student apathy was responsible for the failure of students to protest the previous tuition increases.
III. Students are not likely to demonstrate over new tuition increases.

(a) I only
(b) II only
(c) I or II but not both
(d) I, II and III
(e) None

Ans. (a)

41. The office staff of XYZ corporation presently consists of three bookeepers--A, B, C and 5 secretaries D, E, F, G, H. The management is planning to open a new office in another city using 2 bookeepers and 3 secretaries of the present staff . To do so they plan to seperate certain individuals who don't function well together. The following guidelines were established to set up the new office

I. Bookeepers A and C are constantly finding fault with one another and should not be sent together to the new office as a team
II. C and E function well alone but not as a team , they should be seperated
III. D and G have not been on speaking terms and shouldn't go together
IV Since D and F have been competing for promotion they shouldn't be a team

1.If A is to be moved as one of the bookeepers,which of the following cannot be a possible working unit.

A.ABDEH
B.ABDGH
C.ABEFH
D.ABEGH

Ans.B

2.If C and F are moved to the new office,how many combinations are possible

A.1
B.2
C.3
D.4

Ans.A

3.If C is sent to the new office,which member of the staff cannot go with C

A.B
B.D
C.F
D.G

Ans.B

4.Under the guidelines developed,which of the following must go to the new office

A.B
B.D
C.E
D.G

Ans.A

5.If D goes to the new office,which of the following is/are true

I.C cannot go
II.A cannot go
III.H must also go

A.I only
B.II only
C.I and II only
D.I and III only

Ans.D

42.After months of talent searching for an administrative assistant to the president of the college the field of applicants has been narrowed down to 5--A, B, C, D, E .It was announced that the finalist would be chosen after a series of all-day group personal interviews were held.The examining committee agreed upon the following procedure

I.The interviews will be held once a week
II.3 candidates will appear at any all-day interview session
III.Each candidate will appear at least once
IV.If it becomes necessary to call applicants for additonal interviews, no more 1 such applicant should be asked to appear the next week
V.Because of a detail in the written applications,it was agreed that whenever candidate B appears, A should also be present.
VI.Because of travel difficulties it was agreed that C will appear for only 1 interview.

1.At the first interview the following candidates appear A,B,D.Which of the follwing combinations can be called for the interview to be held next week.

A.BCD
B.CDE
C.ABE
D.ABC

Ans.B

2.Which of the following is a possible sequence of combinations for interviews in 2 successive weeks

A.ABC;BDE
B.ABD;ABE
C.ADE;ABC
D.BDE;ACD

Ans.C

3.If A ,B and D appear for the interview and D is called for additional interview the following week,which 2 candidates may be asked to appear with D?

I. A
II B
III.C
IV.E

A.I and II
B.I and III only
C.II and III only
D.III and IV only

Ans.D

4.Which of the following correctly state(s) the procedure followed by the search committee

I.After the second interview all applicants have appeared at least once
II.The committee sees each applicant a second time
III.If a third session,it is possible for all applicants to appear at least twice

A.I only
B.II only
C.III only
D.Both I and II

Ans.A

43. A certain city is served by subway lines A,B and C and numbers 1 2 and 3
When it snows , morning service on B is delayed
When it rains or snows , service on A, 2 and 3 are delayed both in the morning and afternoon
When temp. falls below 30 degrees farenheit afternoon service is cancelled in either the A line or the 3 line,
but not both.
When the temperature rises over 90 degrees farenheit, the afternoon service is cancelled in either the line C or the
3 line but not both.
When the service on the A line is delayed or cancelled, service on the C line which connects the A line, is delayed.
When service on the 3 line is cancelled, service on the B line which connects the 3 line is delayed.

Q1. On Jan 10th, with the temperature at 15 degree farenheit, it snows all day. On how many lines will service be
affected, including both morning and afternoon.

(A) 2
(B) 3
(C) 4
(D) 5

Ans. D

Q2. On Aug 15th with the temperature at 97 degrees farenheit it begins to rain at 1 PM. What is the minimum number
of lines on which service will be affected?

(A) 2
(B) 3
(C) 4
(D) 5

Ans. C

Q3. On which of the following occasions would service be on the greatest number of lines disrupted.

(A) A snowy afternoon with the temperature at 45 degree farenheit
(B) A snowy morning with the temperature at 45 degree farenheit
(C) A rainy afternoon with the temperature at 45 degree farenheit
(D) A rainy afternoon with the temperature at 95 degree farenheit

Ans. B

44. In a certain society, there are two marriage groups, red and brown. No marriage is permitted within a group. On marriage, males become part of their wives groups; women remain in their own group. Children belong to the same group as their parents. Widowers and divorced males revert to the group of their birth. Marriage to more than one person at the same time and marriage to a direct descendant are forbidden

Q1. A brown female could have had

I. A grandfather born Red
II. A grandmother born Red
III Two grandfathers born Brown

(A) I only
(B) III only
(C) I, II and III
(D) I and II only

Ans. D

Q2. A male born into the brown group may have

(A) An uncle in either group
(B) A brown daughter
(C) A brown son
(D) A son-in-law born into red group

Ans. A

Q3. Which of the following is not permitted under the rules as stated.

(A) A brown male marrying his father's sister
(B) A red female marrying her mother's brother
(C) A widower marrying his wife's sister
(D) A widow marrying her divorced daughter's ex-husband

Ans. B

Q4. If widowers and divorced males retained their group they had upon marrying which of the following would be permissible ( Assume that no previous marriage occurred)

(A) A woman marrying her dead sister's husband
(B) A woman marrying her divorced daughter's ex-husband
(C) A widower marrying his brother's daughter
(D) A woman marrying her mother's brother who is a widower.

Ans. D

Q5. I. All G's are H's
II. All G's are J's or K's
III All J's and K's are G's
IV All L's are K's
V All N's are M's
VI No M's are G's

45. There are six steps that lead from the first to the second floor. No two people can be on the same step
Mr. A is two steps below Mr. C
Mr. B is a step next to Mr. D
Only one step is vacant ( No one standing on that step )
Denote the first step by step 1 and second step by step 2 etc.

1. If Mr. A is on the first step, Which of the following is true?
(a) Mr. B is on the second step
(b) Mr. C is on the fourth step.
(c) A person Mr. E, could be on the third step
(d) Mr. D is on higher step than Mr. C.

Ans: (d)

2. If Mr. E was on the third step & Mr. B was on a higher step than Mr. E which step must be vacant
(a) step 1
(b) step 2
(c) step 4
(d) step 5
(e) step 6

Ans: (a)

3. If Mr. B was on step 1, which step could A be on?
(a) 2&e only
(b) 3&5 only
(c) 3&4 only
(d) 4&5 only
(e) 2&4 only

Ans: (c)

4. If there were two steps between the step that A was standing and the step that B was standing on, and A was on a higher step than D , A must be on step

(a) 2
(b) 3
(c) 4
(d) 5
(e) 6

Ans: (c)

5. Which of the following is false

i. B&D can be both on odd-numbered steps in one configuration
ii. In a particular configuration A and C must either both an odd numbered steps or both an even-numbered steps
iii. A person E can be on a step next to the vacant step.

(a) i only
(b) ii only
(c) iii only
(d) both i and iii

Ans: (c)

46. Six swimmers A, B, C, D, E, F compete in a race. The outcome is as follows.
i. B does not win.
ii. Only two swimmers separate E & D
iii. A is behind D & E
iv. B is ahead of E , with one swimmer intervening
v. F is a head of D

1. Who stood fifth in the race ?
(a) A
(b) B
(c) C
(d) D
(e) E

Ans: (e)

2. How many swimmers seperate A and F ?
(a) 1
(b) 2
(c) 3
(d) 4
(e) cannot be determined

Ans: (d)

3. The swimmer between C & E is
(a) none
(b) F
(c) D
(d) B
(e) A

Ans: (a)

4. If the end of the race, swimmer D is disqualified by the Judges then swimmer B finishes in which place
(a) 1
(b) 2
(c) 3
(d) 4
(e) 5

Ans: (b)

47. Five houses lettered A,B,C,D, & E are built in a row next to each other. The houses are lined up in the order A,B,C,D, & E. Each of the five houses has a colored chimney. The roof and chimney of each housemust be painted as follows.
i. The roof must be painted either green,red ,or yellow.
ii. The chimney must be painted either white, black, or red.
iii. No house may have the same color chimney as the color of roof.
iv. No house may use any of the same colors that the every next house uses.
v. House E has a green roof.
vi. House B has a red roof and a black chimney

1. Which of the following is true ?
(a) At least two houses have black chimney.
(b) At least two houses have red roofs.
(c) At least two houses have white chimneys
(d) At least two houses have green roofs
(e) At least two houses have yellow roofs

Ans: (c)

2. Which must be false ?
(a) House A has a yellow roof
(b) House A & C have different color chimney
(c) House D has a black chimney
(d) House E has a white chimney
(e) House B&D have the same color roof.

Ans: (b)

3. If house C has a yellow roof. Which must be true.
(a) House E has a white chimney
(b) House E has a black chimney
(c) House E has a red chimney
(d) House D has a red chimney
(e) House C has a black chimney

Ans: (a)

4. Which possible combinations of roof & chimney can house
I. A red roof 7 a black chimney
II. A yellow roof & a red chimney
III. A yellow roof & a black chimney

(a) I only
(b) II only
(c) III only
(d) I & II only
(e) I&II&III

Ans: (e)

48. Find x+2y
(i). x+y=10
(ii). 2x+4y=20

Ans: (b)

49. Is angle BAC is a right angle
(i) AB=2BC
(2) BC=1.5AC

Ans: (e)

50. Is x greater than y
(i) x=2k
(ii) k=2y

Ans: (e)

Dell Desktop Interview Question

2008-11-05T10:06:00.002+05:30

1) How many logical drives is it possible to fit into a physical disk?

A) 24 Drives

2) What is maximum hard disk size for FAT 16 based Windows system?

A) 2 GB

3) What is the speed and device maximum specs for fire wire?

A) IEEE 1394 (Fire Wire) support the maximum of 63 connected devices with speed

up to 400 Mbps

4) Where MBR is located on the disk?

A) Master (main) Boot Record is located in sector 0, track 0, head 0, cylinder 0 of the

primary partition.

5) What is difference between L1 and L2 Cache?

A) L1 is internal to the chip and L2 is external.

L1 Cache store information for use by the processor.

L1 Cache is extremely quick but also expensive.

L1 Cache divided into space for data and space for instruction.

L2 Cache is the next step down from L1 cache

Most processor has L2 Cache which increases Cache performance.

Most desktop have an L2 Cache of about 256 Kb.

Some high end processors have as much as 2 Mb.

6) Name the processor lines of two major manufactures?

A) 1) High End

INTEL: Pentium (2nd 3rd 4)

AMD: Athlon

2) Low End:

INTEL: Celeron, Itanium

AMD: Duron, 64bit, Opteron

7) Where the real mode on the CPU comes?

A) The original 8086, which only had 1 MB of memory, these Mega bytes is split into

low memory and high memory.

8) How does you clear CMOS password?

A) Since CMOS is special chips with its own battery, the best way to clear out CMOS

chip is to disconnect it from its power supply. Or remove the CMOS battery for 5

minutes.

Another method to remove CMOS password is by changing jumper from pin 1,2 to

2,3 and then switch on computer for 20 seconds and again change jumper setting to

default 1,2

9) Explain the three way hand shaking of IP?

A) 1) 1st the computer send HELLO packet with the source and destination MAC

address.

2) The 2nd computer send acknowledgement by ARP (Address Resolution

Protocol) with the packet adding with source IP address.

3) The 3 rd way is the 1st system send acknowledgement with the own IP address.

10) What do you understand by IPSEC?

A) It create a secure connection between source to destination machine (machine)

11) Expand (Write the full form of following)

A) SMTP: Simple Mail Transfer Protocol

POP3: Post Office Protocol version 3

IMAP: Internet Messaging Authentication Protocol

NNTP: Network News Transfer Protocol

12) What is the difference between Windows XP professional and Windows 2000

professional?

A) XP 2000

1) Firewall 1) No Firewall

2) Start menu and Start menu Classic 2) Only start menu Classic

3) System Restore 3) Not available

4) ASR backup 4) Emergency Disk

5) Switch user 5) Not available

13) What is difference between Windows XP Home and Windows XP Professional?

A) HOME:

1) Does not support NTFS.

2) Disk quota not available

3) Permissions are not available

4) Dynamic disk is not available

5) No firewall

14) What are four flavors of Windows XP operating system?

A) 1) Home Edition

2) Media Center Edition

3) Professional Edition

4) 64 bit Edition

15) What are four installation methods of Windows XP?

A) 1) Attended Method

2) Unattended Method

3) Remote installation Server method (RIS)

4) System Preparation (Sys Prip)

16) What are minimum requirement for Windows XP installation?

A) Processor speed 330 MHz

RAM: minimum 128 Mb

: Microsoft Recommended 256 Mb

Hard Disk Space: minimum 2 GB

: Microsoft recommended 3.5 to 4 GB

Display: VGA (Video Graphic Array) (640*480)

CD ROM /W

Keyboard

Mouse

17) What are the three types of BASIC disk partition?

A) 1) Primary Partition

2) Extended Partition

3) Logical Drives

18) Explain FAT 16 file system?

A) FAT stand for File Allocation Table

Cluster Size 16 bits

Maximum partition capacity 2.2 GB

Volume size 10GB

Support for Windows 95 and Windows 98

19) Explain FAT 32 File system?

A) FAT stands for File Allocation Table

Cluster size 32 bits

Maximum Partition size 46 GB

Volume size 2 TB

Support for Windows 98, Millennium, NT, 2000 Server / Professional, XP and

2003 Server

20) Explain NTFS file system?

A) NTFS stand for New Technology File System

Cluster size 64 bits

Volume size 2 TB

Support for Windows NT, 2000 Server, XP, 2003 Server

21) What are new features of XP over 2000?

A) 1) Support for 32 bit and 64 bit application

2) Support for Super VGA (Video Graphic Array)

3) New concept Plug and Play (PnP)

22) What is full form of UDP and TCP?

A) UDP: User Datagram Protocol

TCP: Transmission Control Protocol

23) What is Difference between Workgroup and Domain?

A) WORKGROUP DOMAIN

1) Limited Computers 1) Unlimited number of Computers

(20 to 25 Computers)

2) Decentralize Network 2) Centralize Network

3) Configure easily 3) Difficult to configure

User A/C and Groups User A/C and Groups

4) Low Security 4) High Security

24) What is main role of Firewall?

A) By using Firewall we restrict the unauthorized network user to access our data or

computer.

5) Define Network?

A) To connect two or more computer for sharing data and resources is called a

network

26) What are the types of network?

A) Two types of network

1) Point to Point (also called as Workgroup) network

2) Server and Client (also called as Domain) network

27) Define Operating system, Types of Operating system and Examples?

A) The interface between user and Computer is called Operating System. Or a first

installed system software on the computer used to communicate between user and

Computer is called Operating System.

There are two types of Operating System

1) Command User Interface. (CUI)

It is operated on command

User can open only one task at a time.

Example: MS-DOS (Microsoft Disk Operating System)

2) Graphical User Interface. (GUI)

It is Multitask operating system.

Example: Windows 95, 98, XP, Vista.

28) Shared permission effected on Network path or Local path

A) Shared permission effected on only Network path

29) NTFS permission effected on Network path or Local path?

A) NTFS permission effected on both Network path and Local path also

30) Explain Defragmentation?

A) The process of store discarded (Fragmented) files into sequence.

31) What is default size of Virtual memory?

A) 1.5 times of physical memory

32) Which key used to open safe mode login?

A) F8

33) How do you increase Virtual memory?

A) Go to

My Computer>>

Right Click>>

Properties>>

Advance>>

Performance>>

Setting>>

Advance>>

Virtual Memory>>

Change>>

34) What is the role of NTDETECT file?

A) NTDETECT.COM Check the computer hardware attributes.

35) Which options are available in windows security logon windows?

A) 1) Lock Computer

2) Log Off

3) Shut Down

4) Change Password

5) Task Manger

6) Cancel

36) If the system performance slow how can you speed it?

A) 1) Remove temporary files and quarantine files.

2) Execute disk defragment tool.

3) Check for Virus and scan the system

4) Check the services and delete the unnecessary services.

5) Check the Virtual memory Size

37) What are the two types of system restore backup and explain it?

A) System Restore available in only XP operating system

Two types of system restore

1) Check Point:

Whenever you make any changes, back will be taken as every default setting

operating system will take the default changes by itself.

2) Restore Point:

It is created manually as administrator will manually restore the setting

38) What is the RUN command to open Remote desktop connection?

A) MSTSC

39) Which users have the permission to access computer remotely?

A) Those users belong to Administrator or Remote Desktop user groups.

40) Name of seven layers in Open System Interconnection model?

A) 1) Application Layer

2) Presentation Layer

3) Session Layer

4) Transport Layer

5) Network Layer

6) Data Link Layer

7) Physical Layer

DELL Interview Question Papers

2008-11-04T11:16:00.002+05:30

1) How to create a user & how many types are there?
A) There are three types of creating user
1) My computer
> right click
> manage
> Local user & groups
> select user
> right click
>new

2) Start
> setting
> Control panel
> select user account
> double click
create account

3) Run
> CMD
>net user >add

2) Which is private IP address?
A) 192.168.0.0 to 192.168.255.255
172.16.0.0 to 172.31.255.255
10.0.0.0 to 10.255.255.255

3) What is IP address?
A) IP is internet Protocol address / 32 bit address (version 4)

4) What is OSI?
A) Open system interconnection

5) What is Firewall?
A) Firewall protecting our network & supporting from unauthorized user

6) LAN- WAN difference?
A) LAN technology is a (Domain) Server & client network. WAN technology is a
forest. (Routers, Switch & internet Connection)

7) What is TCP/IP?
A) It is an oriented connection protocol, every IP in the WAN.

8) What is Workgroup & Domain?
A) Workgroup is called as a point to point or pear to pear connection. Domain is
server & Client network.

9) What is Network?
A) A connection between two computers is called a network.
Network is divided in two groups
1) Workgroup / point to point / pear to pear
2) Domain / Server & Client

10) What is USB?
A) Universal Serial Bus connection. It can support up to 127 devices like keyboard,
Mouse cellophane.
+/- 5volts DC will be provided to Keyboard.

11) What is DNS?
A) DNS is a Domain Name Server, Will call it as a name server, it translate name to
IP address.

12) What is DHCP?
A) DHCP is Dynamic Host Configuration Protocol. This belongs to TCP service.
DHCP is divided in to
1) Server 67 port No.
2) Client 68 port No.

13) How many types of server there?
A) There are five types of server
1) Application server
2) Data base server
3) File server
4) Web server
5) Print server

14) What is IIS?
A) IIS is Internet Information Service

15) What is operating system?
A) It is set of process (running program) which provides as platform for the user to
run resources (Example= Printer, H.D.D)

16) What is Stage?
A) Stage is set of protocol

17) Expand the RADIUS?
A) Remote Authentication Dill In User Service

18) What is STP?
A) Shielded Twisted Pair Insulation will be thicker. It is always used as a back bone

19) Expand the FAT?
A) File Allocation Table (& it is 32 bit Application) Max support for 48 Gb

20) What is NTFS? & Expand
A) NTFS is New Technology File System platform size is 2TB. Windows 95 &
Windows 98 does not support NTFS

21) What is SAM?
A) SAM is Security Account Manager (this folder store the user account information)

22) What is SID?
A) SID is security identification (it is store the password) It is for your local user.

23) What is Domain?
A) In server we can able to create an account that particular account we can login on
any system in the network.
Store path will be store in this folder
C:\windows\ntdc\log

24) What is NIC?
A) Network Interface Card (NIC or LAN card) we also called as LAN card

25) What is UNC?
A) Universal Naming Conversation path

26) What is MSTSC?
A) Microsoft Terminal Service Client & Console. This command is used for open the
remote access

27) What is Hyperthreding?
A) We can copy the existing setting and when booting time we can get the same
booting setting.

28) What is POST?
A) Power On Self Test. 1st setting (process) of the booting.

29) What is difference between IDE & SATA with respect to data transfer scheme?
A) IDE SATA
1) 40 pins connector (female) 1) 7 cable connector
2) Speed 130 mbps 2) Speed 450 mbps
3) 5200 rpm 3) 7200 rpm
4) We can connect up to 4 devices 4) We can connect up to 6 devices
5) Technology parallel 5) Technology serial

30) What is Dual core?
A) Two core is inters prated on one processor

31) Can a system POST without RAM and Why?
A) No Because
POST> BIOS> HDD> RAM (>PROCESSOR>) RAM> O/P

32) Can system POST without HDD & why?
A) No, Because
POST> BIOS> HDD> RAM> (PROCESSOR) >O/P

33) Types of Hard Disks available in market?
A) 1) PATA
2) SATA
3) SCSI

34) What is PCMCIA?
A) Personal Computer Memory Card International Association
It is memory card used in laptops

35) Can DVD combo burn the DVD disk? Explain?
A) No, DVD combo can burn CD only & read only DVD.

36) What is Stand by?
A) Logically the process will be continued but physically computer will be stopped
functional. When we use Keyboard or mouse it will start again.

37) What is System Restore?
A) System restore will be stored setting, by using this we can system restore to earlier
time

38) Can two operating system stored in single partition?
A) Yes, we can name as it windows1 & windows2

39) How many primary partitions can you create?
A) We can create 4 primary partitions in the hard disk

40) What is the main purpose to creating extended partition?
A) To increase the partition size.

41) Are we able to use the shared network resources in safe mode in windows?
A) No

42) What is difference between windows repair and recovery console? Explain?
A) We can copy all the files in repair but recovery console is used to copy only the
missed files.

Data Structure Quiz

2008-11-02T16:33:00.000+05:30

Data Structure Quiz

1. A 3-D row major order array A [1:u1, 1:u2, 1:u3] has the base address α. If every element occupies n words of m/y, find the address of the element A [i, j, k].

2. Which among the following doesn’t work like a stack
a. Browsing the Internet
b. Opening the multiple windows
c. Playing the multistage game
d. Undo in the text editor

3. If the expression A + (B * C * (D /E ↑ F)) were converted to postfix equivalent using stacks, No of Push & Pop operations required will be …………….

4. Use the Ackerman’s function given below to find the value of A(2,2)
A(m,n) = n+1 if m=0
A(m,n) = A(m-1, 1) if m! = 0, n = 0
Am,n) = A(m-1, A(m, n-1)) if m!= 0, n! = 0

5. If a double ended queue is Input restricted as well as Output restricted, it becomes
a. Linear queue
b. Priority queue
c. Circular queue
d. It does not behave like a queue

6. If a circular linked list of size n were broken from the mid to form two different linked list of approximately the same length, effort required for the same will be
a. O(n)
b. O(1)
c. O(nlogn)
d. O(n2)

7. Dynamic implementation of linked list is preferred than array representation (static) because the former makes the efficient m/y utilization. However there are some situation like ………………, in which static implementation is also preferred.
a. Distributed system
b. Networked system
c. Real time system
d. None of these

8. Linked implementation of a particular graph occupies …………. m/y than adjacency matrix representation.
a. Equal
b. More
c. Less
d. Less than or equal

9. Linked list can not be applicable for
a. Josephus Problem
b. Procedure Call
c. Calculators
d. Air traffic simulation

10. In the linked representation of polynomials, one header node is also used that contains invalid information. If the structure of a node is as given below, what will be the value of Coef & Exp part?
Coef Exp Next

11. Given an ordered circular list of size n. Insertion of x at the appropriate position in the list requires …………. Time
a. O(n)
b. O(log n)
c. O(1)
d. None of these

12. If two polynomials of degree one & n terms are represented in the form of linked list, the multiply operation of these polynomials requires …………. Time
a. O(n)
b. O(n3)
c. O(nlogn)
d. O(n2)

13. Which of the following statement is false with respect to almost complete binary tree of depth d
a. Any node at level less that d-1 has two child
b. Any node in the tree with a right descendant at level d, must have its left descendant also.
c. Any node in the tree with a left descendant at level d, must have its right descendant also.
d. It can be used in the construction of Binary heap

14. A binary tree with 106 nodes has the minimum depth equal to
a. 10
b. 5
c. 7
d. 6

15. The expression tree for A + (B – C * D / E) ↑ (F * G - H) has depth
a. 4
b. 5
c. 6
d. 7

16. Which among the following is not true for a mirror similar binary trees
a. If one is empty other one is also empty
b. Their left subtrees are mirror similar and right subtrees are also mirror similar to each other
c. Left subtree of one tree is mirror similar to right subtree of the other
d. Right subtree of one tree is mirror similar to left subtree of the other

17. Let a binary search tree contains duplicate numbers. The duplicate numbers are kept on the right subtree of the original. What is the time required to insert such a duplicate value in the binary tree with n nodes
a. O(n)
b. O(nlogn)
c. O(1)
d. O(og n)

18. In the binary tree given below, find which node points to which node using thread

19. Given an algorithm to find the inorder traversal of a binary tree. What changes are required to be made for this algorithm to work for finding no of nodes in the tree?
Inordertraverse(tree)
{
if(tree!=NULL)
{
Inordertraverse(left(tree));
write(info(tree));
Inordertraverse(right(tree));
}
}

20. A set of elements are stored as Binary search tree. Write a sequence of instructions to find the nodes in sorted sequence

21. A binary tree with nodes n (t) is converted to extended binary tree with nodes e (t). What is the relation between n (t) & e (t)?

22. n distinct 3-digit numbers are sorted using Radix sort method. What is the maximum no of queue operations performed for the same
a. 2n
b. 3n
c. 6n
d. n

23. If searching is performed on the ordered table of size n where the keys are uniformly distributed between Key(1) – Key(n), which of the following techniques will require least effort
a. Sequential search
b. Index sequential search
c. Binary search
d. Interpolation search

24. Pick the odd one out
a. Open addressing
b. Separate chaining
c. Linear Hashing
d. Rehashing

25. Pick the odd one out
a. Dijikstra’s Algorithm
b. Ford – Fulkerson’s Algorithm
c. Bellman Ford algorithm
d. Huffman algorithm

Answers

1. α + [(i-1)*u2*u3 + (j-1)*u3 + (k-1)] * n
2. c
3. Push – 7, POP – 7
4. 7
5. c
6. a
7. c
8. b
9. b
10. coef – 0, exp – (-1)
11. a
12. d
13. c
14. c
15. b
16. b
17. d
18.
a. J points to B
b. D points to C
c. I points to A
d. H points to I
e. F points to E
19.
Inordertraverse(tree, static n)
{
if(tree!=NULL)
{
Inordertraverse(left(tree));
n=n+1;
Inordertraverse(right(tree));
}
}
20.
Procedure sorted_BST
1. Find the minimum of the tree using procedure min (let min node is p), print this node
2. Find the inorder successor of node p and print the node
3. Repeat 2 until no inorder successor can be found.

21. e (t) = 2* n (t) + 1
22. c
23. d
24. c
25. d