2001 prentice hall, inc. all rights reserved. 1 chapter 23 - bluetooth™ wireless technology...

2001 Prentice Hall, Inc. All rights reserved.

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Chapter 23 - Bluetooth™ Wireless Technology

Outline23.1 Introduction23.2 History of Bluetooth Wireless Technology23.3 Bluetooth Special Interest Group (SIG)

23.3.1 SIG Membership23.3.2 Product Qualification

23.4 Bluetooth Wireless Communications Technology23.5 Profiles

23.5.1 Generic Access Profile23.5.2 Service Discovery Application Profile23.5.3 Serial Port Profile23.5.4 Cordless Telephony Profile23.5.5 Intercom Profile23.5.6 Headset Profile23.5.7 Dial-Up Networking Profile23.5.8 Fax Profile23.5.9 Local Area Network (LAN) Access

Profile


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Chapter 23 - Bluetooth™ Wireless Technology

23.5.10 Generic Object Exchange Profile23.5.11 Object Push Profile23.5.12 File Transfer Protocol Profile23.5.13 Synchronization Profile

23.6 Piconets and Scatternets23.7 Bluetooth Security23.8 Other Wireless Networks: 802.11b and HomeRF23.9 Devices and Applications23.10 Future of Bluetooth Wireless Technology23.11 Case Study: Introduction to Bluetooth Programming

23.11.1 Bluetooth Chat Application23.11.2 Host Controller Interface (HCI)23.11.3 Inquiry Stage23.11.4 Connection23.11.5 Service Discovery23.11.6 COM Connection

23.12 Internet and World Wide Web Resources


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23.1 Introduction

• BluetoothTM wireless technology enables communications between computers and various devices, reducing and even eliminating the need for wires.

• Bluetooth wireless technology creates personal area networks (PANs)– Devices search, or page, the surrounding area (up to 30 feet)

for other devices which they can communicate with and contact

• May be one of the fastest growing wireless communications technologies


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23.1 Introduction

• Many obstacles face Bluetooth wireless technology– security concerns

– high costs

– manufacturer support

– complex programming (based in lower levels of application development at the present time)


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23.2 History of Bluetooth Wireless Technology

• Conceived in 1994 by Telefonaktiebolaget LM Ericsson based in Stockholm, Sweden– Examined using low-power, short-range radio frequencies

for wireless communications between devices

• Two famous people connected with Bluetooth– King Harald Blatland, 10th century Viking King of Denmark

(Blatland translates to Bluetooth in English)

– Hedy Lamarr, an actress that helped George Antheil discover frequency hopping technology (frequencies should “hop” around on various communications channels because they are harder to intercept)


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23.3 Bluetooth Special Interest Group (SIG)

• Formed in 1998 by Ericsson, IBM, Intel, Toshiba and Nokia to develop a standard for Bluetooth wireless technolgy

• Membership benefits– access to other member companies’ patents and technologies

• Membership constraints– must conform to SIG-qualification testing

– all information must be shared to advance the technology


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23.3.1 SIG Membership

• Over 2000 companies participate in SIG• 3 levels

– Promoter

– Associate

– Adopter

• Each level has different fees and different offerings– Promoter level is the highest but costs the most, also has

non-restricted access to all technologies and specifications

– Adopter membership is free but access to certain SIG information is limited


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23.3.1 SIG Membership

Promoter Company Bluetooth Site

3Com www.3com.com

Agere www.lucent.com/micro/bluetooth/

Ericsson www.ericsson.com/bluetooth

IBM www.ibm.com

Intel www.intel.com/mobile/technology/wireless.htm

Microsoft www.microsoft.com/hwdev/bluetooth

Motorola www.motorola.com/bluetooth

Nokia www.nokia.com/bluetooth/

Toshiba www.toshiba.com

Fig. 23.1 Bluetooth SIG promoter members and their Web addresses.


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23.3.2 Product Qualifications

• All products must pass qualification for a company to apply the Bluetooth trademark to a product– ensures interoperability

– Developers follow profiles and usage models to build applications• profiles define different types of behaviors that devices containing

Bluetooth technology use to communicate

• Testing performed by members called Bluetooth Qualification Bodies at Bluetooth Qualification Testing Facilities

• Bluetooth Qualification Program Reference– controlling document for all product qualifications and

requirements

• Not all products have the same qualification process


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23.4 Bluetooth Wireless Communications Technology

• Protocol stack: set of technological rules that developers implement to achieve Bluetooth capabilities

• 7 layers– Bluetooth Radio layer is at the bottom of the protocol stack

– Radio signals are at the core of Bluetooth

– Every Bluetooth module includes radio transceiver

– Baseband layer provides technical settings to enable receiving and sending of radio signals and is a core protocol

– Link Manager, another core protocol, sets up a communications link on a Bluetooth device, configures it and performs security functions (such as authentications)


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23.4 Bluetooth Wireless Communications Technology– Host Controller Interface (HCI) produces a bridge over

which the host computer communicates with lower level protocol

– Logical Link Control and Adaptation Layer Protocol (L2CAP) provides data services to upper-layer protocols

– RFComm layer emulates the signal by which serial ports receive and process data

• uses Service Discover Protocol (SDP) and Telephony Control Protocol (TCS)

– Last layer comprised of various existing protocols


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23.4 Bluetooth Wireless Communications Technology

Fig. 23.2 Bluetooth protocol stack and the OSI layers.

Telephony Contro l (TC S)/RFC OMM/Service Disc overy (SDP)

1. Physical Layer

2. Data Link Layer

3. Network Layer

4. Transport Layer

5. Session Layer

6. Presentation Layer

7. Application Layer

OSI Model

Bluetooth Radio

Various Existing Protocols

Bluetooth Protoco l Stack

Baseband

Link Manager

Logical Link Contro l and Adaptation (L2CAP)

Host C ontroller Interfac e


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23.5 Bluetooth Profiles

• Profiles define specification and usage of Bluetooth wireless technology– profiles may reuse part of or reference another profile

– profiles can share security, user interfaces and procedures, and specify the order in which procedures can combine

• All profiles are built using the Generic Access Profile


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23.5 Profiles

Bluetooth Version 1.1 Profiles and Usa ge Models Generic Usage Profiles

Generic Access

Service Discovery Application

Generic Object

Serial Port

Specific Profiles and Usage Models

Headset Profile/3-in-1 Phone and Ultimate Headset Usage Models

Dial-up Networking Profile

Fax Profile

LAN Access Profile and Internet Bridge Usage Model

Intercom Profile/3-in-1 Phone Usage Model

Exchange Profile

Object Push Profile

File Transfer Profile and Usage Model

Synchronization Profile and Usage Model

Fig. 23.3 Bluetooth profiles and corresponding usage models.


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23.5 Profiles

Fig. 23.4 Relationships and interdependence of Bluetooth profiles. (Courtesy of The Bluetooth SIG, Inc.)


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23.5.1 Generic Access Profile

• Generic Access Profile: provides developers with basic settings for all other profiles– guidelines for establishing contact with Bluetooth devices

– offers technical descriptions of setting modes

– documents definitions, recommendations and requirements for procedures

– covers establishing links and sets the user interface requirements for Bluetooth wireless devices

– defines security level for the device


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23.5.2 Service Discovery Application Profile

• Service Discovery Application Profile (SDAP): sets level of investigation that a Bluetooth-enabled device can perform when inquiring about other Bluetooth-enabled device services

• Defines features and procedures for applications that discover services registered in other devices

• Describes how to retrieve desired available information for those services

• Covers how a device requests a certain service or whether it can browse a menu of services on other devices


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23.5.3 Serial Port Profile

• Serial Port Profile: acts as a technical base for 8 other profiles

• Defines the protocols and procedures that will allow a device to emulate a signal transmission of a serial port cable


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23.5.4 Cordless Telephony Profile

• The Cordless Telephony Profile defines interoperability requirements of the 3-in-1 Phone Usage Model


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23.5.5 Intercom Profile

• Intercom Profile: supports the Walkie-Talkie Usage Model, which defines requirements for Bluetooth devices that support intercom functionality within the 3-in-1 phone case

• Limited because of its focus on the Cordless Telephony Profile


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23.5.6 Headset Profile

• Headset Profile: supports the Ultimate Headset Usage Model

• Defines how a cordless headset can connect to a cell phone or another other hands-free communications device


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23.5.7 Dial-Up Networking Profile

• Dial-Up Networking Profile: allows a device to use a mobile phone as a modem to connect to a network


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23.5.8 Fax Profile

• Fax Profile: defines how to program various devices to send faxes


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23.5.9 Local Area Network (LAN) Access Profile

• Local Area Network (LAN) Access Profile: defines how Bluetooth devices establish a connection to a LAN through access points and function as if they had a dial-up connection

• Defines computer to computer connection to a LAN and multiple Bluetooth devices


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23.5.10 Generic Object Exchange Profile

• Generic Object Exchange Profile: defines protocols for transferring data or objects over


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23.5.11 Object Push Profile

• Object Push Profile: defines using a device such as a cell phone to push, or send, data without an initial request from another device– data can be text or audio

• Defines pulling an object from another device

– pulling based on a device request


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23.5.12 File Transfer Protocol Profile

• File Transfer Protocol Profile: supports client and server abilities to browse another device’s file system and transfer files and folders to between the devices


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23.5.13 Synchronization Profile

• Synchronization Profile: supports exchange or updating information to different devices– Scenarios include cell phones, PDAs or PCs.

• Defines how data synchronizes without user commands when two Bluetooth-enabled devices come within range of each other


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23.6 Piconets and Scatternets

• Connected Bluetooth devices form piconets

• Interconnected piconets form scatternets, which form as Bluetooth devices move through an area

• Bluetooth communications– point-to-point: one master device (device that initiates inquiries to

other devices) communicates with one slave device (responding device)

– point-to-multipoint: one master device can communicate with up to seven slave devices in the piconet

• Devices can act as both a master or a slave device– device address: unique 48-bit number assigned to the device when

manufactured• device address of a master device determines the frequency-hopping

pattern and the slave device synchronizes to the sequences


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23.6 Piconets and Scatternets

• Bluetooth devices communicate over the 2.4 GHz Industrial, Scientific and Medical (ISM) spectrum through frequency hopping

• Frequency hopping reduces interferences, power consumption and lowers costs as compared to other transmission methods– Low-powered modes of Bluetooth devices include park,

hold and sniff


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23.7 Bluetooth Security

• Security issues are a major concern for Bluetooth wireless technology

• Bluetooth SIG recommends trust levels: Trusted Device Level and Untrusted Device Level

• Bluetooth uses secret-key cryptography– initialization key

– link key

• Core protocols address security issues and settings– Generic Access Profile defines 3 security modes

• Security Mode 1

• Security Mode 2

• Security Mode 3


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23.8 Other Wireless Networks: 802.11b and HomeRF

• 802.11b is intended for college campus and corporate use– transmission speeds can reach 11Mbps

– transmission range can reach up to 300 feet

– supports data transmissions on the 2.4GHz spectrum

• HomeRF developed for home networks (e.g., SOHOs)– supports up to 128 devices

– tranmission speeds can reach 1-2Mbps

– supports data and voice transmissions on 2.4GHz spectrum

– tranmission range up to 300ft

• 802.11b and Bluetooth transmissions interfere with one another which causes technical difficulties


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23.9 Devices and Applications

• Over 250 products on the market since the year 2000

• Bluetooth possibilities could be endless– enables the creation of wireless offices, link computers via

LANs, connect mice and keyboards to PCs without cables, connect PCs to printers

– could link cell phones to ATMs

– Bluetooth Local Information Point (BLIP) could allow stores or kiosks to send advertisements

– Bluetooth PC Cards


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23.9 Devices and Applications

• Examples of Companies developing Bluetooth services and devices– IBM offers a adhoc network simulator

– ThinAirApps Inc. is developing technology to enable wireless users to view corporate data and print it remotely

– Axis Communications is collaborating with Classwave to produce wireless e-mail, Internet access and m-commerce transactions solutions

– Microsoft, Palm Inc. and others are building devices such as PDAs to support Bluetooth


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23.10 Future of Bluetooth Wireless Technology

Possible Bluetooth Applications 1. Phones or PDAs could deliver airline information while the user walks through the airport. 2. Promotions could be sent to a wireless device as a user passes by a store. 3. Bluetooth phones could talk to a digital camera, sending picture attachments in text messages. 4. A laptop could communicate wirelessly to an office projector to run presentations. 5. Teams can collaborate on projects without having to share a network. 6. Theater and sports events will not require people to have paper tickets. 7. Internet access could be delivered anywhere in airports. 8. Bluetooth all-purpose home/work phone can place calls over the most advantageous network available in an area. Phones or handhelds will carry a users credit card and bank information. 10. Smart kiosks could deliver information to a Bluetooth device. Many people could access a kiosk at one time. 11. Remove wires from a workplace. 12. Print from a cell phone without wires. 13. A mechanic can scan an automobile’s computer to diagnose mechanical problems. 14. Clothes dryers could notify users’ cell phones when clothes are dry. 15. One device could control a home thermostat, lights and change television channels.

Fig. 23.5 Examples of future Bluetooth applications.


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23.11 Case Study: Introduction to Bluetooth Programming

• Bluetooth training available through Ericsson and Teleca Comtec at the Bluetooth Academy


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23.11.1 Bluetooth Chat Application

List of Devices

List of Servic es Message Input Fie ld

Message Fie ld

List of Activities

Device ID Selec ted Device ID

Selec ted Device

Fig. 23.6 Bluetooth chat application interface.

2001 prentice hall, inc. all rights reserved. 1 chapter 23 - bluetooth™ wireless technology...

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