Bluetooth: What is it?

Bluetooth, what is it and how does it work?                                                

What is Bluetooth?

Bluetooth wireless technology is a short range communications technology intended to replace the cables connecting  portable and or fixed devices while maintaining high levels of security, operating in the unlicensed ISM band at 2.4 Ghz. It allows real time AV and data communications between bluetooth enabled hosts.

What does ISM stand for?

ISM stands for industrial, scientific and medical (ISM). ISM radio bands were originally reserved internationally for the use of RF electromagnetic fields for industrial, scientific and medical purposes other than communications. In general, communications equipment must accept any interference generated by ISM equipment.

Where does the name Bluetooth come from?

The Bluetooth Special Interest Group (SIG) is a privately held, not-for-profit trade association founded in September  1998. Bluetooth started as the code name for the association when it was first formed and the name stuck. The name  "Bluetooth" is from the 10th century Danish King Harald Blatand - or Harold Bluetooth in English. King Blatand was instrumental in uniting what is now Norway, Sweden, and Denmark. Bluetooth technology is designed to allow collaboration between differing industries such as the computing, mobile phone, and automotive markets.

What does the Bluetooth version number signify?

Bluetooth technology devices include a specification, or version number. The major releases over the 10 years that Bluetooth technology has been available include 1.0, 1.1, 1.2, 2.0 and the newest specification, 2.1 + EDR. Each release has offered greater ease of use, speed, reliability and security. As a general rule, products are backward compatible with earlier versions (for instance a 2.0 device can work with 1.1 devices, but not the other way around.) For the best results, products of the same version number should be used together.

What is a Bluetooth enabled device?

A Bluetooth enabled device is a device that is capable of short-range wireless communications using the Bluetooth protocols.

How far can Bluetooth enabled devices communicate?

Although there are many factors that can influence performance, Bluetooth enabled devices typically offer a range of up to 10m of connectivity and a transfer rate between about 400 and 700 kbit/s. Some networking devices are capable of much greater distances.

How many Bluetooth enabled devices can I connect at one time?

Up to seven devices can belong to one piconet at a time. But, each device can belong to multiple piconets, so there is virtually no limit to the number of devices that can communicate with each other. In practice hands free car kits generally operate with a single connection although it is feasible to have several and some manufacturers provide this functionality.