Bluetooth Fever

Bluetooth is an industrial specification for wireless personal area networks.Bluetooth provides a way to connect and exchange information between devices such as mobile phones,laptops, PCs, printers, digital cameras, and video game consoles over a secure, globally unlicensed short-range radio frequency. The Bluetooth specifications are developed and licensed by the Bluetooth Special Interest Group.

Bluetooth wireless headsets hit the market in 2000 and early adopters drew strange stares and spare change in their coffee mugs, as they appeared to talk to themselves. Fortunately, it didn't take long for mainstream consumers to understand the convenience and benefits of Bluetooth headsets and adopt them as a part of common culture. Today, more than three-quarters of American consumers are familiar with Bluetooth technology, and Bluetooth headsets are one of the most popular mobile phone accessories.

A personal computer that does not have embedded Bluetooth can use a Bluetooth adapter that enables the PC to communicate with Bluetooth devices. While some desktop computers and most recent laptops come with a built-in Bluetooth radio, others require an external adapter, typically in the form of a small USB "dongle."

 Bluetooth implements confidentiality, authentication and key derivation with custom algorithms based on the SAFER block cipher. In Bluetooth, key generation is generally based on a Bluetooth PIN, which has to be entered into both devices. This procedure might get modified slightly, if one of the devices has a fixed PIN, which is the case e.g. for headsets or similar devices with a restricted user interface. Foremost, an initialization key or master key is generated, using the E22 algorithm.

There is a master Bluetooth device which can communicate with up to seven devices. This network group of up to eight devices is called a piconet, using Bluetooth technology protocols to allow one master device to interconnect with up to seven active devices. Up to 255 further devices can be inactive, or parked, which the master device can bring into active status at any time.At any given time, data can be transferred between the master and one other device, however, the devices can switch roles and the slave can become the master at any time. The master switches rapidly from one device to another in a round-robin fashion. (Simultaneous transmission from the master to multiple other devices is possible, but not used much.)Bluetooth specification allows connecting two or more piconets together to form a scatternet, with some devices acting as a bridge by simultaneously playing the master role and the slave role in one piconet.Older Bluetooth adapters, however, have limited services, offering only the Bluetooth Enumerator and a less-powerful Bluetooth Radio incarnation. Such devices can link computers with Bluetooth, but they do not offer much in the way of services that modern adapters do.