From M/Cyclopedia of New Media
Bluetooth- Technical Introduction:
- In the first couple of years of Bluetooth, the devices themselves did not come imbedded in the appliances like mobile phones and PDAs (Personal Digital Assistants), they had to be added on to the particular appliance. These days, however, many digital appliances are coming with Bluetooth as standard. [Bray and Sturman, p. 443] Bluetooth is a wireless technology based on radio waves. These short-range radio waves are used primarily to replace cables when connecting devices to each other, whether they are portable or fixed. [Ganguli, p. 7] Bluetooth is seen as “connective convenience� [Gupta, p.1] where there are no hassles in connecting several cables to many devices, which has many home and office computer desks cluttered. The use of radio waves ensures that there is no need to have a line of sight to connect devices, and radio waves can penetrate wall and other solid objects. Also, unlike some other wireless technologies, Bluetooth can handle both voice and data transmissions. It has a range of up to ten metres, and this is constantly being improved on. [Gupta, p. 1] Its low power consumption demonstrates that it has been designed with portable devices in mind, so that it won’t exhaust battery life in an appliance like a mobile phone. [Gupta, p. 2]
- Bluetooth technology uses the “unlicensed, Industrial- Scientific Medical (ISM) band… for transmissions that varies with a change in location.� [Ganguli, p. 25-6] This specific band is also known as the 2.4 GHz spectrum and it is used worldwide and recognised accordingly as an unlicensed band. For Bluetooth this means that it can be used in almost every country, and has no charge like traditional telecommunications companies. Even though the 2.4 GHz spectrum is unlicensed, there are guidelines for its use, such as that interference should be reduced as much as possible and “appropriately handled.� [Miller and Bisdikian, p. 17]
- Bluetooth uses ‘frequency hopping’ to ensure uninterrupted connections. This means that it jumps around on the bandwidth at around sixteen hundred times per second, to make sure the connection is authentic and to prevent interruptions. [Ganguli, p. 26] Frequency hopping “avoid[s] interference from other signals by hopping to a new frequency after transmitting or receiving a packet.� [Gupta, p. 2]
- To pair two or more Bluetooth devices, one of the Bluetooth devices act as a master and the other as a slave. These connections are known as “point- to- point links� and “point- to- multipoint links,� depending on whether the master unit is connecting to one or more devices. [Ganguli, p. 96] During these pairing connections, each device is “designated master or slave.� [Swaminatha and Elden, p. 49] There are no set designations for this, and either or any of the devices may be the master or slave. [Swaminatha and Elden, p. 49] Bluetooth is especially proficient at creating and maintaining ‘ad hoc’ networks, which are networks that are formed “spontaneously.� [Miller and Bisdikian, p. 44] This is especially convenient for office meetings.
- Security measures within Bluetooth devices are sufficient but as yet not without fault. Each Bluetooth device is assigned a separate 48-bit address, which is authenticated whenever two Bluetooth devices come in contact with each other. Users of Bluetooth devices are also offered varying security layers, depending on the strictness of the security that they want for their device.
Bibliography:
- Bray, J and Sturman, C. 2001. Bluetooth Connect without Cables, New Jersey: Prentice- Hall, Inc. ISBN 0130898406
- Ganguli, M. 2002. Getting Started with Bluetooth, Ohio: Premier Press. ISBN 1931841837
- Gupta, P. 1999. Bluetooth Technology: What are the Applications?. http://www.mobileinfo.com/Bluetooth/applic.htm (accessed August 23, 2004).
- Miller, B and Bisdikian, C. 2001. Bluetooth Revealed, United States of America: Prentice- Hall, Inc. ISBN 0130672378
- Swaminatha, T. and Elden, C. 2003. Wireless Security and Privacy: Best Practices and Design Techniques, Massachusetts: Pearson Education, Inc. ISBN 0201760347
Bluetooth- Security
Erin Watson 19:16, 27 Oct 2004 (EST)
