Monday, November 1, 2004

Bluetooth, a commercial application of mobile ad-hoc network

WIRELESS INFRASTRUCTURE

By Humayun Bakht

Wireless cellular networks have been in use since the early eighties. We have seen first, second, and third generation wireless systems. In future wireless systems, there will be a need for the rapid deployment of mobile users. It's relatively hard to have such instant network formation within the existing frame of a single hop or fixed wireless system.

This fact has motivated the wireless community to review the old theme of the "on-the-fly" or ad-hoc network. The idea of ad-hoc networking goes back to the DARPA (Defense Advanced Research Projects Agency) packet radio network, which was in used in 1970's. A mobile ad-hoc network is a collection of mobile devices establishing a short live or temporary network in the absence of a supporting structure. Mobile ad-hoc networks can be used in establishing efficient, dynamic communication for rescue, emergency, and military operations. A commercial application, such as Bluetooth, is one of the recent developments utilizing the concept of ad-hoc networking.

Bluetooth is named after a King: Harald Blat (translated as Bluetooth in English). Bluetooth was first introduced in 1998. Bluetooth uses radio waves to transmit wireless data over short distances. Bluetooth can support many users in any environment. Eight devices can communicate with each other in a small network known as piconet. At one time, ten of these piconets can coexist in the same coverage range of the Bluetooth radio. A Bluetooth device can act both as a client and a server. A connection must be established to exchange data between any two Bluetooth devices. In order to establish a connection a device must request a connection with the other device.

Bluetooth was based on the idea of advancing wireless interactions with various electronic devices. Devices like mobile phones, personal digital assistants, and laptops with the right chips could all communicate wirelessly with each other. However, later it was realized that a lot more is possible.

For instance, if data transmission between a computer and a printer is possible, then why couldn't the same be done between a personal digital assistant and a printer or from a mobile phone to a printer. At present, Bluetooth technology is in used in a variety of different places. Not long ago, in May 2004, a service knows as BEDD was launched in Singapore. BEDD uses Bluetooth wireless communications to scan strangers' phones for their personal profiles. Once the software is downloaded into a compatible phone, it automatically starts searches for and exchanges profiles with other phones that come within a 20-meter radius.