Introduction to Bluetooth technology
- 1. BLUETOOTH TECHNOLOGY Group B Maj Marek Sipko Capt Billy Hortman Capt Michael McFerron LT Mark Bjerke LTjg David Jackson
- 2. Bluetooth A specification adopted by the world's most powerful and influential communications and computer manufacturers. It will enable devices from mobile phones and PCs to camcorders and cookers to talk to one another.
- 4. A little bit of history: In early 1994, a team of researchers led by Sven Mattisson and Jaap Haartsen in a vibrant college town called Lund, Sweden, were investigating the possibility of developing a wireless connection between an ear-piece and phone. As development proceeded, with it came the realization that the potential of such a technology far exceeded that of a mere cordless headset. Ericsson decided to further research the technology and thus, almost by accident the Bluetooth concept was born.
- 5. The Bluetooth SIG set the following goals: Global usage Voice and data handling The ability to establish ad-hoc connections The ability to withstand interference from other sources in the open band Very small size, in order to accommodate integration into a variety of devices Negligible power consumption in comparison to other devices for similar use An open interface standard Competitively low cost of all units, as compared to their non-Bluetooth contemporaries.
- 6. So how does Bluetooth work? Basically, Bluetooth works by finding out what other Bluetooth devices are nearby and then talking to them as necessary. It does this by establishing a piconet, where one device controls communications with up to seven others. Many piconets can be linked to form a scatternet .
- 7. Some ideas on how Bluetooth will ingratiate itself into our lives: Data synchronization need never again be a problem as your Bluetooth enabled PDA, PC or laptop all talk to each other and update their respective files to the most recent ones. Traveling in a plane, a person may write but not send e-mail. When the plane touches down the Bluetooth enabled laptop will communicate with the user's phone and will automatically send them. Mice and keyboards will identify themselves to the computer without intervention, or could also be used to command TVs, videos or hi-fis at the touch. Use e-mail while your laptop is still in the briefcase! When your laptop receives e-mail, you'll get an alert on your mobile phone. You can also browse all incoming e-mails and read those you select in the mobile phone's display. A traveling businessperson could ask his laptop computer to locate a suitable printer as soon as he enters a hotel lobby, and send a printout to that printer when it has been found.
- 8. The Reality Check In truth, Bluetooth is merely complementary to the other technologies that permeate our lives. A universal communicator, in itself it is of little benefit, but combined with our mobile phones, PDAs and other devices, it becomes a potent technology.
- 9. The Killer App for Bluetooth The eradication of wire clutter
- 10. SECURITY ISSUES Bluetooth’s abilities, for the moment at least, will be limited to domestic use. As unresolved security issues continue to loom, it is only a brave or stupid end-user that would adopt Bluetooth on anything but a trivial scale.
- 11. Domestic arena offers Bluetooth a bright future People have a natural and healthy dislike for cables littering their floors, and a technology that eliminates such an eyesore and tedium for not only computers but other electronic equipment like stereo’s, TV sets, home kitchen and others.
- 12. Data Synchronization The bane of those who work on the same projects and files on different devices should be made almost ridiculously easy by Bluetooth. Merely having the different devices - PC, laptop, PDA, whatever - within about 10 meters of each other should suffice as they all automatically update their copy to the most recent one.
- 13. The Radiation Issues It is a matter of concern to some that the carrier waves used by Bluetooth inhabit the same band as that of microwave ovens. Fortunately, the transmitting power is far too weak to result in perceptible effects in humans. Moreover, the radiation is not concentrated in a single beam; rather, it is randomly dispersed in all directions.
- 14. Security Issues and Bluetooth The three principal security features employed by Bluetooth are: Frequency hopping, thus making eavesdropping almost impossible. Authentication, allowing a user to control connectivity to specified devices only. Encryption, utilizing a 0-bit, 40-bit or 64-bit key. Despite considerable investment in this area, significant security holes still exist in the 1.1 implementation of Bluetooth.
- 15. The Real Security Threat A more real concern lies in the method needed to establish piconets. The necessity of PIN code entry in the initialization process of two Bluetooth devices is sloppy at best. The problem is augmented if each device in a scatternet or larger-sized piconet has to be independently initialized. It also poses significant problems for a network administrator - it is unlikely that a unique PIN would be assigned to each device, but not doing so would seriously compromise network integrity. It is worth noting that the SIG maintain that hackers would have to take "extreme measures" to perform this kind of hacking.
- 16. Security Bottom Line Bluetooth in its current form is unsuitable for the transfer of sensitive data. The Bluetooth SIG is actively seeking to implement more sophisticated security protocols.
- 17. Tech Specs Frequency Range Physical Layer Noise Immunity Error Control Data Transmission Power
- 18. Frequency Range Bluetooth devices utilize the 2.4Ghz Industrial, Scientific, and Medical (ISM) frequency range. Throughout most of the world this band is free and unregulated. Encouraged by the Bluetooth SIG, governments worldwide are now beginning to regulate the 2.4Ghz band, thus ensuring that it will remain available for unhindered use by Bluetooth appliances.
- 19. Physical Layer The Bluetooth hardware is comprised of a single 9*9mm chip. Inserted into any device it can communicate with any other Bluetooth device within a 10m radius, or up to 100m if an amplifier is used. The maximum data rate achievable by 1st generation technology is 1Mbps. Bluetooth appliances use Gaussian Frequency Shift Keying (GSSK) for radio frequency modulation. Judicious use of these modulation techniques should allow future generations to achieve a transfer rate of between 2 and 12Mbps.
- 20. Noise Immunity Frequency Hop (FH) spread spectrum is a method which effectively divides the frequency band into a number of hop channels. A technology that quickly hops channels minimizes potential interference. Bluetooth takes advantage of this technique by incorporating a fast frequency hopping technology with a nominal hopping rate of 1600 hops/second among 79 channels. After transmitting a packet each device hops to another frequency as determined by the master. The hopping sequence is unique to each piconet and determined by the Bluetooth Device Address (BDA) of the piconet master.
- 21. Frequency Hop (FH) Spread Spectrum
- 22. Error Control Another method by which Bluetooth increases its noise immunity is that of Forward Error Correction (FEC). FEC is a method that enables a receiver to not only detect but also correct errors in a transmission. This technique is especially valuable in limiting the impact of noise on long distance links. Three error correction techniques have been so far defined in the Bluetooth specification: 1/3 Rate FEC 2/3 Rate FEC Automatic Repeat Request (ARQ)
- 23. Data Transmission Bluetooth allows for data to be transmitted either synchronously or asynchronously. The Synchronous Connection Oriented (SCO) method is used primarily for voice while the Asynchronous Connectionless (ACL) method is used for data. Since SCO packets need smooth transmission, they are transmitted via reserved intervals, i.e. packets sent in groups with no interrupts.
- 24. Power Bluetooth is truly admirable for its sparing use of power. The technology limits the transmitter's power output to exactly that needed - the signal strength is dynamically modified to suit the required range. Power saving modes examined in the Bluetooth protocol provide further benefits.
- 25. Bluetooth Connection Protocol The Bluetooth connection protocol describes the set of rules by which all Bluetooth devices must abide in order to establish a link and communicate with one another. The essence of Bluetooth is based upon dynamically configured units. Hopping very quickly between frequencies, the protocol specifically caters for many different modes to allow for minimal power consumption.
- 26. Standby Devices not connected in a piconet are in standby mode. In this mode, they listen for messages every 1.28 seconds - over 32 hop frequencies (fewer in Japan, Spain, and France due to local bandwidth regulation).
- 27. Page/Inquiry If a device wishes to make a connection with another device, it sends out a page message if the address is known, or an inquiry followed by a page message if it is unknown. The master unit sends out 16 identical page messages on 16 hop frequencies to the slave unit. If there is no response, the master retransmits on the other 16 hop frequencies. The inquiry method requires an extra response from the slave unit, since the MAC address is unknown to the master unit.
- 28. Active Simply, data transmission occurs.
- 29. Hold When either the master or slave wishes, a hold mode can be established, during which no data is transmitted. The purpose of this is to conserve power. Otherwise, there is a constant data exchange. A typical reason for going into hold mode is the connection of several piconets .
- 30. Sniff The sniff mode, applicable only to slave units, is for power conservation, though not at as reduced a level as hold. During this mode, the slave does not take an active role in the piconet, but listens at a reduced level. This is usually a programmable setting.
- 31. Park Park mode is a more reduced level of activity than the hold mode. During it, the slave is synchronized to the piconet, thus not requiring full reactivation, but is not part of the traffic. In this state, they relinquish their MAC addresses , but only listen enough to keep their synchronization with the master and check for broadcast messages.
- 32. FUTURE OF BLUETOOTH Bluetooth was never designed to be a system competing with LAN. It rather complements LAN, but taken as it is, Bluetooth is a competent technology offering unparalleled convenience. Ending, it will provide means to get rid of connecting wire, and this is a truly a killer app for it.