BLUETOOTH

Bluetooth wireless technology is a de facto standard for low-cost, short-range, radio linkS between mobile PCs, mobile phones, and other portable devices. The Bluetooth specifications are released by the Bluetooth Special Interest Group (SIG), an industry group consisting of industrial leaders in the telecommunications, computing, and networking.

The IEEE 802.15 Working Group for Wireless Personal Area Networks has
started a project to publish and approve a standard derived from the Bluetooth specification.

The Bluetooth system operates in the 2.4 GHz industrial, scientific, and medicine
(ISM) band. It is based on a low-cost, short-range radio link integrated into a microchip, enabling protected ad hoc connections for wireless communication of voice and data in stationary and mobile environments. It enables use of mobile data in different ways for different applications. Due to its low-cost target, it can be envisaged that Bluetooth microchips will be embedded in all consumer electronic devices.

 The Bluetooth Network

From a logical standpoint, Bluetooth belongs to the contention-free, token-based multiaccess networks. In a Bluetooth network, one station has the role of master and all other Bluetooth stations are slaves. The master decides which slave is the one to have access to the channel. The units that share the same channel (i.e., are synchronized to the same master) form a piconet, the fundamental building block of a Bluetooth network. A piconet has a gross bit rate of 1 Mbps that represents the channel capacity before considering the overhead introduced by the adopted protocols and polling scheme. A piconet contains a master station and up to seven active (i.e., participating in data exchange) slaves simultaneously.
Independent piconets that have overlapping coverage areas may form a scatternet.