1. by Santosh Sam Koshy

2. Agenda Need for Bluetooth Brief History of Bluetooth Introduction to Bluetooth Bluetooth System Specifications Commercial Bluetooth Solutions Network of Bluetooth Devices Data and Voice support Security Issues in Bluetooth Architecture of a Bluetooth System References

3. Need for Bluetooth Due to the widespread use of computers and other electronic gadgets at home and at office, the work place is now a labyrinth of wires, and will still get worse. This is a problem that has to be ministered as soon as possible The Solution: Bluetooth Cable Replacement

4. The Solution

5. History of Bluetooth Named after a medieval Danish King The Bluetooth Special Interest Group (SIG) was founded in February 1998 by Ericsson, Intel, IBM, Toshiba and Nokia The Bluetooth specification version 1.0 was released in July1999 and version 1.1 in February 2001

6. Introduction to Personal Area Networks A typical office is equipped with a number of devices such as a PC, laptop, printer, fax, modem and so on.. These devices are interconnected by wires for the purpose of sharing information. They form a Personal Area Network (PAN). The PAN is an ad-hoc network because the number of nodes in the network is not fixed at any time. Administering to these networks will be easier in using radio links for communication. A number of technologies have been proposed for the same such as Bluetooth, IrDA, IEEE-802.11.. Of which Bluetooth is the most attractive choice

7. Bluetooth System Specifications Operating Frequency The Bluetooth operating frequency is 2400 – 2483.5MHz Bluetooth radio uses Frequency Hopping and hops between channels @ 1600 hops per second Unless the receiver knows the hop sequence, it cannot receive data Bluetooth radios communicate using a time division duplex (TDD) discipline. More than 2 devices may share the medium, and is therefore a TDMA Thus it may be said that Bluetooth uses FH-TDD-TDMA

8. Bluetooth System Specifications (contd..) Operating Range The normal operating range for Bluetooth is 10 meters The range is dependent on the power of the radio transmitter – the higher the power, the higher the range The Bluetooth specs define 3 classes wrt the operating range

9. Services Supported Bluetooth supports both voice and data services Since voice communication is done in circuit switching mode and data communication is done in packet switching mode, both types of connections are supported in Bluetooth The link established for voice communication is a Synchronous Connection Oriented (SCO) link, and the link established for data communication is a Asynchronous Connection Less (ACL) link.

10. Network Topology In a PAN, a set of devices forms a piconet (a small network) In each piconet, there is on master, to which all other devices (slaves) tune to. The master decides the hop-frequency sequence and the slaves synchronize with the master to establish links Any device can become a master/slave. for example, a cellular phone can be master or slave to a desktop

11. Network Topology: Piconet

12. Forming a Piconet

13. Establishing A Connection

14. Master Slave Piconet

15. Scatternets

16. Commercial Bluetooth Solutions Bluetooth headset Bluetooth cordless phone Bluetooth LAN access point Bluetooth LCD projector Bluetooth speakers

17. Core and Profile Specifications The Core Specifications describe the details of the various layers of the Bluetooth protocol architecture, from the radio interface to the link control The Profile Specifications are concerned with the use of Bluetooth technology to support various applications. Each profile discusses the use of technology defined in the core specifications to implement a particular usage model

18. Why Profiles???? The purpose of a profile specification is to define a standard of interoperability, so that products from different vendors that claim support to a particular usage model will work together. Profile Specification Cable ReplacementWireless Audio

19. Bluetooth Protocol Stack f AT Commands Bluetooth Radio Baseband Link Manager Protocol Logical Link Control and Adaptation Protocol (L2CAP) RFCOMM TCS BinSDP Audio Control vCard OBEX WAE WAP UDP/TCP IP PPP Host Controller Interface TCS Core Protocols Cable Replacement Adopted

20. Protocol Architecture The core protocols form a five layer stack containing : Radio Specifies details of air interface, including frequency, the use of frequency hopping, modulation scheme, and transmit power Baseband Concerned with the connection establishment within a piconet, addressing, packet format, timing and power control Link Manager Protocol (LMP) Responsible for the link setup between Bluetooth devices and ongoing link management

21. Protocol Architecture (contd..) Logical Link Control and Adaptation Protocol (L2CAP) Adapts the upper layer protocols to the baseband layer. Provides both connectionless and connection-oriented services. Service Discovery Protocol (SDP) Device information, services, and the characteristics of the services can be queried to enable the establishment of a connection between two or more Bluetooth devices

22. Protocol Architecture (contd..) RFCOMM is the cable replacement protocol included in the Bluetooth specification. RFCOMM emulates a serial port that is designed to make replacement of cable technologies Bluetooth specifies a telephony control protocol. TCS BIN is a bit oriented protocol that defines the call control signaling for the establishment of speech and data calls between Bluetooth devices

23. Protocol Architecture (contd..) The adopted protocols include PPP The point to point protocol in the internet is standard protocol for transporting IP datagrams over a point to point link TCP/UDP/IP Foundation protocols of the TCP/IP protocol suite OBEX Protocol developed by the Infrared Data Association (IrDA), for the exchange of objects WAE/WAP Bluetooth incorporates the above too

24. Bluetooth and OSI

25. Bluetooth Functional Block Diagram

26. Bluetooth State Transition Diagram Connection Standby Page Scan Inquiry Scan Inquiry Response Slave Response Master Response

27. Bluetooth States Standby Default state. Only clock is running Connection The device is connected to the piconet as master or slave Page Device has issued a page. Used by master to activate and connect to a slave Page Scan Device is listening for a page

28. Bluetooth States Master Response Master receives a page response from a slave Slave Response Slave responds to a page from master Inquiry Device has issued an inquiry Inquiry Scan Device is listening for an inquiry Inquiry Response Device that issued inquiry receives response

29. In a Jist 1. Device sends an inquiry using a special inquiry – hopping sequence 2. Inquiry scanning devices respond by sending a packet 3. The inquiring device requests a connection to the device that responded 4. Paging is used to initiate the connection with the selected device 5. The selected device which has entered the page scan state responds 6. It synchronizes with the master’s timing and FH sequence

30. References William Stallings, Wireless Communications and Networks, Pearson Education, 2004 Dreamtech Software Team, Cracking the Code, Hungry Minds IDG Books India (P) Ltd, November 2001