Bluetooth

1. Bluetooth By Gaffmaster and Tucker

2. Where does Bluetooth get it’s name • Harald Bluetooth was king of Denmark in the late 900s. He managed to unite Denmark and part of Norway into a single kingdom then introduced Christianity into Denmark. He left a large monument, the Jelling rune stone, in memory of his parents. He was killed in 986 during a battle with his son, SvendForkbeard. Choosing this name for the standard indicates how important companies from the Nordic region (nations including Denmark, Sweden, Norway and Finland) are to the communications industry, even if it says little about the way the technology works.

3. How does Bluetooth Work • 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). This frequency band has been set aside by international agreement for the use of industrial, scientific and medical devices (ISM).

4. How it works Continued • Bluetooth uses a technique called spread-spectrum frequency hopping that makes it rare for more than one device to be transmitting on the same frequency at the same time. In this technique, a device will use 79 individual, randomly chosen frequencies within a designated range, changing from one to another on a regular basis. In the case of Bluetooth, the transmitters change frequencies 1,600 times every second, meaning that more devices can make full use of a limited slice of the radio spectrum. Since every Bluetooth transmitter uses spread-spectrum transmitting automatically, it’s unlikely that two transmitters will be on the same frequency at the same time. This same technique minimizes the risk that portable phones or baby monitors will disrupt Bluetooth devices, since any interference on a particular frequency will last only a tiny fraction of a second.

5. Manufactures • Bluetooth is managed by the Bluetooth Special Interest Group, which has more than 18,000 member companies in the areas of telecommunication, computing, networking, and consumer electronics. The SIG oversees the development of the specification, manages the qualification program, and protects the trademarks. To be marketed as a Bluetooth device, it must be qualified to standards defined by the SIG. A network of patents is required to implement the technology and are licensed only for those qualifying devices.

6. What is Bluetooth used in? • Phones TV Computers Wireless Headsets Gaming Consoles

7. Why was Bluetooth Created • Created by telecom vendor Ericsson in 1994, it was originally conceived as a wireless alternative to RS-232 data cables. It can connect several devices, overcoming problems of synchronization.

8. History 1998 • The Bluetooth special interest group (SIG) is formed. SIG is a group of companies that have Bluetooth in their products and seek to make and keep Bluetooth functioning. • Bluetooth is given its official name

9. History 1999 Bluetooth 1.0 specs are released (these generally sucked) Slow transmission speeds Becomes backward compatible

10. History 2000 First headset is designed and utilizes Bluetooth technology The first mobile phone to feature Bluetooth comes to the market First PC card features Bluetooth

11. History 2001 • Printer, Laptop, hands-free car kit, all become • Bluetooth enabled • SIG is now a privately held trade association

12. History 2002 Keyboard and mouse combo, gps receiver, digital camera all are Bluetooth enabled devices

13. History 2003 MP3 player and the first FDA approved medical system is approved.

14. History 2004 Version 2.0 is released which introduces EDR (enhanced data rate) Pairing is improved

15. History 2005 Bluetooth is really popular now! Yay!

16. History 2006 First sunglasses, watch, and picture frame are now possible with Bluetooth

17. History 2007 First alarm clock and television PTS protocol viewer is released

18. History 2008/2009 • Version 3.o is released- better transmission • speeds, MAC/PHY or the physical layer of bluetooth (the antenna and chip) and alternatives are released • for transmission (they kick in when your • sending large data)

19. History 2010 3d television is now using Bluetooth V4 is released-includes classic Bluetooth, high speed Bluetooth, and low power Bluetooth specs. Security improves IPhone 4s is the first phone to feature v4

20. History 2012 Tablets hit the world with the newest Bluetooth technology

21. Missing info • Bluetooth 1.x -> Nearly extinct; if at all you find a device which is advertised as 1.x - don't buy that relic, unless of course you want it as a collectors item.Capabilities - Basic ratebluetooth (that would be about a theoretical maximum of 1 Mbps data rate)Bluetooth 2.x -> The most popular variant, especially 2.1. The 2.1 version makes it easier to pair with different devices (even from different manufacturers) and also increases the reliability per se of the pairing process. Introduced the Enhanced Data Rate (EDR) capability (optional).Capabilities - Basic rate + EDR (that would be about a theoretical maximum of 3 Mbps data rate; optional)Bluetooth 3.x -> Introduces support for an alternate lower layer, i.e. all the applications that were available with Bluetooth radio earlier can be run over an alternate radio, say like the 802.11 one. This feature is called High Speed (HS), and as the name suggests that was the intent and purpose. The HS feature is optional too.Capabilities -  Basic rate + EDR (optional) + HS (optional)Bluetooth 4.x -> Introduces support for collecting data from devices which generate data at a very low rate. The main intent of this feature, called Low Energy (LE), is to aggregate data from various sensors, like heart rate monitors, thermometers etc.

22. Missing info • Legacy pairing: This is the only method available in Bluetooth v2.0 and before. Each device must enter a PIN code; pairing is only successful if both devices enter the same PIN code. Any 16-byte UTF-8 string may be used as a PIN code; however, not all devices may be capable of entering all possible PIN codes. • Limited input devices: The obvious example of this class of device is a Bluetooth Hands-free headset, which generally have few inputs. These devices usually have a fixed PIN, for example "0000" or "1234", that are hard-coded into the device. • Numeric input devices: Mobile phones are classic examples of these devices. They allow a user to enter a numeric value up to 16 digits in length. • Alpha-numeric input devices: PCs and smartphones are examples of these devices. They allow a user to enter full UTF-8 text as a PIN code. If pairing with a less capable device the user needs to be aware of the input limitations on the other device, there is no mechanism available for a capable device to determine how it should limit the available input a user may use. • Secure Simple Pairing (SSP): This is required by Bluetooth v2.1, although a Bluetooth v2.1 device may only use legacy pairing to interoperate with a v2.0 or earlier device. Secure Simple Pairing uses a form of public key cryptography, and some types can help protect against man in the middle, or MITM attacks. SSP has the following characteristics: • Just works: As implied by the name, this method just works. No user interaction is required; however, a device may prompt the user to confirm the pairing process. This method is typically used by headsets with very limited IO capabilities, and is more secure than the fixed PIN mechanism which is typically used for legacy pairing by this set of limited devices. This method provides no man in the middle (MITM) protection. • Numeric comparison: If both devices have a display and at least one can accept a binary Yes/No user input, they may use Numeric Comparison. This method displays a 6-digit numeric code on each device. The user should compare the numbers to ensure they are identical. If the comparison succeeds, the user(s) should confirm pairing on the device(s) that can accept an input. This method provides MITM protection, assuming the user confirms on both devices and actually performs the comparison properly. • Passkey Entry: This method may be used between a device with a display and a device with numeric keypad entry (such as a keyboard), or two devices with numeric keypad entry. In the first case, the display is used to show a 6-digit numeric code to the user, who then enters the code on the keypad. In the second case, the user of each device enters the same 6-digit number. Both of theses cases provide MITM protection. • Out of band (OOB): This method uses an external means of communication, such as Near Field Communication (NFC) to exchange some information used in the pairing process. Pairing is completed using the Bluetooth radio, but requires information from the OOB mechanism. This provides only the level of MITM protection that is present in the OOB mechanism. • SSP is considered simple for the following reasons: • In most cases, it does not require a user to generate a passkey. • For use-cases not requiring MITM protection, user interaction can be eliminated. • For numeric comparison, MITM protection can be achieved with a simple equality comparison by the user. • Using OOB with NFC enables pairing when devices simply get close, rather than requiring a lengthy discovery process.

23. Missing info • RFCOMM • Radio Frequency Communications (RFCOMM) is a cable replacement protocol used to create a virtual serial data stream. RFCOMM provides for binary data transport and emulates EIA-232 (formerly RS-232) control signals over the Bluetooth baseband layer, i.e. it is a serial port emulation. • RFCOMM provides a simple reliable data stream to the user, similar to TCP. It is used directly by many telephony related profiles as a carrier for AT commands, as well as being a transport layer for OBEX over Bluetooth. • Many Bluetooth applications use RFCOMM because of its widespread support and publicly available API on most operating systems. Additionally, applications that used a serial port to communicate can be quickly ported to use RFCOMM.

24. Missing info How far it can transmit data • Class 1 100 Meters • Class 2 10 Meters • Class 3 1 Meter

26. Sources • en.wikipedia.org/wiki/Bluetooth • www.howstuffworks.com/bluetooth.htm