Bluetooth
Bluetooth, also known as the IEEE 802.15.1 standard is based on a wireless radio system designed for short-range and cheap devices to replace cables for computer peripherals, such as mice, keyboards, joysticks, and printers. This range of applications is known as wireless personal area network (WPAN). Bluetooth attempts to provide significant advantages over other data transfer technologies, such as IrDA and Home RF, vying for similar markets. Despite comments from the Bluetooth SIG indicating that the technology is complementary to IrDA, it is clearly a competitor for PC-to-peripheral connection. IrDA is already popular in PC peripherals, but is severely limited by the short connection distance of 1 m and the line-of-sight requirement for communication. This limitation eliminates the feasibility of using IrDA for hidden computing, where the communicating devices are nearby but not visible to one another. Due to its RF nature, Bluetooth is not subject to such limitations. In addition to wireless device connections up to 10 m (up to 100 m if the transmitter’s power is increased), devices need not be within line of sight and may even connect through walls or other nonmetal objects. This allows for applications such as a cell phone in a pocket or a briefcase acting as a modem for a laptop or PDA. [2]