Thursday, November 09, 2006


In Blue tooth has some disadvantage in receiving signal when it comes distance from the reciever.I knew some of techie geeks has to stand and beeline to mobile eventhough the equiped with Bluetooth enabled connective device..Its a great setback to Bluetooth..Wi-Fi replace this setback..Go ahead here

Wi-Fi (also WiFi, wifi, etc.) is a brand originally licensed by the Wi-Fi Alliance to describe the underlying technology of wireless local area networks (WLAN) based on the IEEE 802.11 specifications. It was developed to be used for mobile computing devices, such as laptops, in LANs, but is now increasingly used for more services, including Internet and VoIP phone access, gaming, and basic connectivity of consumer electronics such as televisions and DVD players, or digital cameras. More standards are in development that will allow Wi-Fi to be used by cars in highways in support of an Intelligent Transportation System to increase safety, gather statistics, and enable mobile commerce .
A person with a Wi-Fi enabled device such as a computer, cell phone or PDA can connect to the Internet when in proximity of an access point. The region covered by one or several access points is called a hotspot. Hotspots can range from a single room to many square miles of overlapping hotspots. Wi-Fi can also be used to create a mesh network. Both architectures are used in community networks, municipal wireless networks like Wireless Philadelphia, and metro-scale networks like M-Taipei.Wi-Fi also allows connectivity in peer-to-peer mode, which enables devices to connect directly with each other.
This connectivity mode is useful in consumer electronics and gaming applications.When the technology was first commercialized there were many problems because consumers could not be sure that products from different vendors would work together. The Wi-Fi Alliance began as a community to solve this issue so as to address the needs of the end user and allow the technology to mature. The Alliance created the branding Wi-Fi CERTIFIED to show consumers that products are interoperable with other products displaying the same branding.

How its working::
A typical Wi-Fi setup contains one or more Access Points (APs) and one or more clients. An AP broadcasts its SSID (Service Set Identifier, "Network name") via packets that are called beacons, which are usually broadcast every 100 ms. The beacons are transmitted at 1 Mbit/s, and are of relatively short duration and therefore do not have a significant effect on performance. Since 1 Mbit/s is the lowest rate of Wi-Fi it assures that the client who receives the beacon can communicate at least 1 Mbit/s. Based on the settings (e.g. the SSID), the client may decide whether to connect to an AP. If two APs of the same SSID are in range of the client, the client firmware might use signal strength to decide which of the two APs to make a connection to. The Wi-Fi standard leaves connection criteria and roaming totally open to the client. This is a strength of Wi-Fi, but also means that one wireless adapter may perform substantially better than the other. Since Wi-Fi transmits in the air, it has the same properties as a non-switched ethernet network. Even collisions can therefore appear as in non-switched ethernet LAN's.

[Examples of Standard Wi-Fi Devices]

Wireless Access Point (WAP)

A wireless access point (AP) connects a group of wireless stations to an adjacent wired local area network (LAN). An access point is similar to an ethernet hub, but instead of relaying LAN data only to other LAN stations, an access point can relay wireless data to all other compatible wireless devices as well as to a single (usually) connected LAN device, in most cases an ethernet hub or switch, allowing wireless devices to communicate with any other device on the LAN.

Wireless Routers

A wireless router integrates a wireless access point with an IP router and an ethernet switch. The integrated switch connects the integrated access point and the integrated ethernet router internally, and allows for external wired ethernet LAN devices to be connected as well as a (usually) single WAN device such as cable modem or DSL modem. A wireless router advantageously allows all three devices (mainly the access point and router) to be configured through one central configuration utility, usually through an integrated web server. Wireless

Ethernet Bridge

A wireless Ethernet bridge connects a wired network to a wireless network. This is different from an access point in the sense that an access point connects wireless devices to a wired network at the data-link layer. Two wireless bridges may be used to connect two wired networks over a wireless link, useful in situations where a wired connection may be unavailable, such as between two separate homes.

Range Extender

A wireless range extender (or wireless repeater) can increase the range of an existing wireless network by being strategically placed in locations where a wireless signal is sufficiently strong and near by locations that have poor to no signal strength. An example location would be at the corner of an L shaped corridor, where the access point is at the end of one leg and a strong signal is desired at the end of the other leg. Another example would be 75% of the way between the access point and the edge of its useable signal. This would effectively increase the range by 75%.

Wi-Fi and its support by operating systems

There are two sides to Wi-Fi support under an operating system. Driver level support and configuration and management support.Driver support is usually provided by the manufacturer of the hardware or, in the case of Unix clones such as Linux and FreeBSD, sometimes through open source projects.Configuration and management support consists of software to enumerate, join, and check the status of available Wi-Fi networks. This also includes support for various encryption methods. These systems are often provided by the operating system backed by a standard driver model. In most cases, drivers emulate an ethernet device and use the configuration and management utilities built into the operating system. In cases where built in configuration and management support is non-existent or inadequate, hardware manufacturers may include their own software to handle the respective tasks.Microsoft WindowsMicrosoft Windows has comprehensive driver-level support for Wi-Fi, the quality of which depends on the hardware manufacturer. Hardware manufactures almost always ship Windows drivers with their products. Windows ships with very few Wi-Fi drivers and depends on the OEMs and device manufactures to make sure users get drivers. Configuration and management depend on the version of Windows.Earlier versions of Windows, such as 98, ME and 2000 do not have built-in configuration and management support and must depend on software provided by the manufacturer Microsoft Windows XP has built-in configuration and management support. The original shipping version of Windows XP included rudimentary support which was dramatically improved in Service Pack 2. Support for WPA2 and some other security protocols require updates from Microsoft. To make up for Windows’ inconsistent and sometimes inadequate configuration and management support, many hardware manufacturers include their own software and require the user to disable Windows’ built-in Wi-Fi support Microsoft Windows Vista is expected to have improved Wi-Fi support over Windows XP. The original betas automatically connected to unsecured networks without the user’s approval. This is a large security issue for the owner of the respective unsecured access point and for the owner of the Windows Vista based computer because shared folders may be open to public access. The release candidate (RC1 or RC2) does not continue to display this behavior, requiring user permissions to connect to an unsecured network, as long as the user account is in the default configuaration with regards to User Account Control.

Microsoft India unveils strategy for ‘Innovative web developing’ at IndiMIX ’06

New Delhi: Microsoft Corporation India Pvt. Ltd. today announced its strategy and products for the ‘next web’ at IndiMIX ‘06, its event for 40,000 web designers, developers and decision-makers.

Steve Ballmer, Microsoft CEO, kicked off the event with a keynote on the myriad ways companies could use software to forge distinctively new types of customer connections, highlighting new technologies along the way that would change the face of business and experiences on the web.

Microsoft and its partners also showcased a range of applications developed on Microsoft’s platform for the web including ASP.NET 2.0, Windows Presentation Foundation with Windows Vista and Microsoft Expression.

In his keynote, Ballmer said, “The Internet is becoming an increasingly powerful way for companies to interact with customers. Software and services provide almost incredible opportunities to enhance these interactions.

“Customers are demanding more interactive and responsive experiences that take full advantage of the capabilities of the web, as well as the multitude of digital touch points that consumers use every day, ranging from the web to the PC to the mobile phone. We, at Microsoft, are committed to innovating in this area,” he added.
Microsoft is devoted to innovate in the web space across a broad range of web technologies. IndiMIX ’06 is a significant milestone in Microsoft’s ongoing investments in this direction. The company recently launched Visual Studio 2005 and Visual Studio Team System, which are powerful tools that enable developers write software for next generation platforms like the web.

Tuesday, November 07, 2006

Indian's Innovative-Stealth Aircraft

Materials scientists at the Indian Institute of Technology in Roorkee (IIT-R) have developed microwave absorbing nanocomposite coatings that could make aircraft almost invisible to radar.
The technology for building invisible, or stealth aircraft, is a closely guarded secret of developed countries and a handful of laboratories in India are doing research in this area.
Radars that emit pulses of microwave radiation identify flying aircraft by detecting the radiation reflected by the aircraft's metallic body. The nanocomposite coatings developed by Rahul Sharma, R.C. Agarwala and Vijaya Agarwala at IIT-R absorb most of the incident radiation and reflect very little.
Sharma, who revealed his team's work at an international nanomaterials conference held recently at the Indian Institute of Science here, believes their nano-product is a significant step in developing a technology to enable aircraft escape radar surveillance and protect its equipment from electronic "jamming".
Nanoparticles -- so called because of their very small size -- are known to exhibit unique physical and chemical properties. The IIT team found that crystals of "barium hexaferrite" with particle size of 10-15 nanometres have the ability to absorb microwaves. (Human hair, for comparison, is 100,000 nanometres thick).
They developed special processes for synthesising the nanopowder and formulating it as a coating.
Sharma said that the nanocomposite coating on the aluminium sheet absorbed 89 percent of incident microwaves at 15 giga hertz - the frequency normally used by radars -- reflecting only 11 percent. A stealth aircraft should ideally absorb all the incident radiation and reflect nothing.

Wednesday, November 01, 2006


Hi Netizens!
In recent days we have been continously keep hearing the word "Bluetooth" technology,as I avid learner of new
technologies in short period,I hunted to gather some infos like these technologies.Please be visit frequently for
knowing what I learned about pros and cons about this new technology..Cheer up!!

The Origin of the Word
The name Bluetooth is derived from the cognomen of a 10th century king of Denmark, Harald Bluetooth. According to the inventors of the Bluetooth technology, Harald engaged in diplomacy which led warring parties to negotiate with each other, making Bluetooth a fitting name for their technology, which allows different devices to talk to each other.
Bluetooth is a radio standard and communications protocol primarily designed for low power consumption, with a short range (power class dependent: 1 metre, 10 metres, 100 metres) based around low-cost transceiver microchips in each device.
Bluetooth lets these devices communicate with each other when they are in range. The devices use a radio communications system, so they do not have to be in line of sight of each other, and can even be in other rooms, so long as the received transmission is powerful enough.
Bluetooth applications
Wireless control of and communication between a cell phone and a hands free headset or car kit. This is the most popular use.
Wireless networking between PCs in a confined space and where little bandwidth is required.
Wireless communications with PC input and output devices, the most common being the mouse, keyboard and printer.
Transfer of files between devices via OBEX.
Transfer of contact details, calendar appointments, and reminders between devices via OBEX.
Replacement of traditional wired serial communications in test equipment, GPS receivers and medical equipment.
For remote controls where infrared was traditionally used.
Sending small advertisements from Bluetooth enabled advertising hoardings to other, discoverable, Bluetooth devices.
Wireless control of a games console, Nintendo's Wii and Sony's PlayStation 3 will both use Bluetooth technology for their wireless controllers.
Sending commands and software to the LEGO Mindstorms NXT instead of infrared.

Future of Bluetooth
The next version of Bluetooth technology, currently code-named Lisbon, includes a number of features to increase security, usability and value of Bluetooth. The following features are defined:
Atomic Encryption Change - allows encrypted links to change their encryption keys periodically, increasing security, and also allowing role switches on an encrypted link.

Extended Inquiry Response - provides more information during the inquiry procedure to allow better filtering of devices before connection. This information includes the name of the device, and a list of services, with other information.

Sniff Subrating - reducing the power consumption when devices are in the sniff low-power mode, especially on links with asymmetric data flows. Human interface devices (HID) are expected to benefit the most, with mice and keyboards increasing the battery life from 3 to 10 times those currently used.

QoS Improvements - these will enable audio and video data to be transmitted at a higher quality, especially when best effort traffic is being transmitted in the same piconet.
Simple Pairing - this improvement will radically improve the pairing experience for Bluetooth devices, while at the same time increasing the use and strength of security. It is expected that this feature will significantly increase the use of Bluetooth.
Bluetooth technology already plays a part in the rising Voice over IP (VOIP) scene, with Bluetooth headsets being used as wireless extensions to the PC audio system. As VOIP becomes more popular, and more suitable for general home or office users than wired phone lines, Bluetooth may be used in Cordless handsets, with a base station connected to the Internet link.
The version of Bluetooth after Lisbon, code-named Seattle, has many of the same features, but is most notable for plans to adopt Ultra-wideband radio technology. This will allow Bluetooth use over UWB radio, enabling very fast data transfers, synchronizations and file pushes, while building on the very low power idle modes of Bluetooth. The combination of a radio using little power when no data is transmitted, and a high data rate radio used to transmit bulk data, could be the start of software radios. Bluetooth, given its worldwide regulatory approval, low power operation, and robust data transmission capabilities, provides an excellent signalling channel to enable the soft radio concept.
On 28 March 2006, the Bluetooth Special Interest Group (SIG) announced its selection of the WiMedia Alliance Multi-Band Orthogonal Frequency Division Multiplexing (MB-OFDM) version of Ultra-wideband (UWB) for integration with current Bluetooth wireless technology. UWB integration will create a version of the globally popular Bluetooth wireless technology with a high speed/high data rate option. This new version of Bluetooth technology will meet the high-speed demands of synchronizing and transferring large amounts of data as well as enabling high quality video and audio applications for portable devices, multi-media projectors and television sets, wireless VOIP. At the same time, Bluetooth technology will continue catering to the needs of very low power applications such as mice, keyboards and mono headsets, enabling devices to select the most appropriate physical radio for the application requirements, thereby offering the best of both worlds.