Bluetooth uses short-range radio waves over distances up to approximately 10 metres. For example, Bluetooth devices such as a keyboards, pointing devices, audio head sets, printers may connect to Personal digital assistants (PDAs), cell phones, or computers wirelessly.
A Bluetooth PAN is also called a piconet (combination of the prefix "pico," meaning very small or one trillionth, and network), and is composed of up to 8 active devices in a master-slave relationship (a very large number of devices can be connected in "parked" mode). The first Bluetooth device in the piconet is the master, and all other devices are slaves that communicate with the master. A piconet typically has a range of 10 metres (33 ft), although ranges of up to 100 metres (330 ft) can be reached under ideal circumstances.
Recent innovations in Bluetooth antennas have allowed these devices to greatly exceed the range for which they were originally designed. At DEF CON 12, a group of hackers known as "Flexilis" successfully connected two Bluetooth devices more than half a mile (800 m) away. They used an antenna with a scope and Yagi antenna, all attached to a rifle stock. A cable attached the antenna to a Bluetooth card in a computer. They later named the antenna "The BlueSniper.
A Bluetooth PAN is also called a piconet (combination of the prefix "pico," meaning very small or one trillionth, and network), and is composed of up to 8 active devices in a master-slave relationship (a very large number of devices can be connected in "parked" mode). The first Bluetooth device in the piconet is the master, and all other devices are slaves that communicate with the master. A piconet typically has a range of 10 metres (33 ft), although ranges of up to 100 metres (330 ft) can be reached under ideal circumstances.
Recent innovations in Bluetooth antennas have allowed these devices to greatly exceed the range for which they were originally designed. At DEF CON 12, a group of hackers known as "Flexilis" successfully connected two Bluetooth devices more than half a mile (800 m) away. They used an antenna with a scope and Yagi antenna, all attached to a rifle stock. A cable attached the antenna to a Bluetooth card in a computer. They later named the antenna "The BlueSniper.
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