What is Bluetooth
- Wireless technology for short-range voice and data communication
- Low-cost and low-power
- The Bluetooth specification was developed as a cable replacement in 1994 by Jaap Haartsen and Sven Mattisson, who were working for Ericsson in Sweden. The specification is based on frequency-hopping spread spectrum technology
- Bluetooth networking transmits data via low-power radio waves. It communicates on a frequency of 2.45 gigahertz (actually between 2.402 GHz and 2.480 GHz, to be exact).
Ad Hoc Networks
- Up to 8 devices can be actively connected in master/slave configuration
- Piconets can be combined to form scatter nets providing unlimited device connectivity
- A master Bluetooth device can communicate with a maximum of seven devices in a piconet.
Bluetooth Protocol Stack
![Bluetooth Protocol Stack]()
Paring and Bonding
- Bluetooth uses a process called bonding, and a bond is generated through a process called pairing. The pairing process is triggered either by a specific request from a user to generate a bond (for example, the user explicitly requests to "Add a Bluetooth device"), or it is triggered automatically when connecting to a service where (for the first time) the identity of a device is required for security purposes. These two cases are referred to as dedicated bonding and general bonding respectively.
Why Bluetooth broadcasting?
- Bluetooth broadcasting will most likely not be able to replace broadcasting systems like television and radio broadcasts, or even message transmission technologies like e-mail, SMS/MMS and instant messengers (one example on instant messengers is MSN Messenger).
- Unlike other digital channels for sending information, Bluetooth broadcasting allows for directing broadcasted information towards all people that are in the area, rather than a group of known people.
- While SMS and MMS messages could to some extent fill the same purpose as Bluetooth broadcasting, using Bluetooth has the additional advantage of being free to use.
- It is not completely free of course, since it will still cost money for the hardware used for broadcasting, and for maintenance.
Bluetooth broadcasting could be used for
- Concert halls, theatres and similar places could broadcast calendar events to inform about future events.
- Museums could broadcast information about opening hours and special events. Inside the museum it could broadcast information about museum items or areas.
- Trains and buses could broadcast information inside the vehicles, for example the list of bus/train stops, travel time, modified vacation schedules, and other information.
Broadcasting station
- A broadcasting station may consist of a computer with one or more Bluetooth dongles, and running a broadcasting application.
- However, it is not always practical to use a computer for broadcasting , depending on where one wants the broadcast to be.
Target devices
- For a Bluetooth broadcasting system, the main targets for the broadcast will be devices that move within range of the broadcast
- Mobile phones
- PDAs (Personal Digital Assistants)
- Laptops
File types
- Text (as TXT files)
- Still images (as GIF or JPG files)
- Animated images (as animated GIF files)
- Audio (as WAV, RMF, MP3, MP4 or ring tone files)
- Video (as RM, 3GP or MP4 files)
- Java Applications (as JAR files)
- vCal (Calendar event files)
Component