In 1994, Ericsson was responsible for a study to find a replacement for cable connections. The name “Bluetooth” is a tribute to the 10th Century living Danish Viking King Harald Bluetooth (Harald Blatand, Eng. Bluetooth).

Bluetooth devices transmit in the unlicensed 2.4 GHz (2.402 to 2.48). Because of using other applications of this frequency band, mutual interference is possible. In particular, wireless can be disrupted by Bluetooth. Bluetooth not. In order to achieve robustness to interference, a frequency hopping (frequency hopping is used).

This frequency-hopping method, the devices all 625 microseconds cycle through 79 different channels at 1 MHz. This creates a Bluetooth chip is not dependent on a specific frequency and so insensitive trouble. For the connection of Bluetooth devices form the device’s own micro-radio cells (so-called Pikonetze). Within such a Pikonetzes is room for eight Bluetooth devices. Within a Pikonetzes a device works as a control station (master), the other devices are the result of stations (slaves). Each Bluetooth chip has the ability to act both as master and as slave in Pikonetz.

In order to authenticate devices can safely be implemented in a Bluetooth Challenge – Response – procedures. Both the master and the slave can make a review. The station sends wishes to authenticate with one of queried LMP_au_rand station a random number. This is calculated with the random number of its own Bluetooth address and a security key for an answer. The stations have a common connection code is a positive sign for the requested station, in the other case, is a negative receipt. Recently, product manufacturers, many vulnerabilities to other Bluetooth devices have closed. But the current security issues relate mainly to mobile phones. Mobile phones and Bluetooth devices can be found at Here are a few tips on how you can improve the Bluetooth security:-Keep confidential data such as your Social Security number, credit card numbers and passwords, never on a Bluetooth device. -Turn off your Bluetooth device into the “non-discoverable” (transmission), and set the “discoverable” mode only when you actually work with it. A device in discoverable mode is always ready for the Bluetooth transmission. This is a big risk;-Use a secure PIN code. Codes with five or more points are harder to crack. -Find out all the latest developments in Bluetooth technology, and security issues, and ask the manufacturer of your device regularly for security updates or specific vulnerabilities.