Wireless Personal and Local Area Networks

ISBN-13: 9780470851104 / Angielski / Twarda / 2003 / 216 str.

Axel Sikora

Opis

Wireless LANs are the 'silver bullet' for networks of the future, allowing small communities of office workers, industrial workers, hospital employees, technical teams, etc. to communicate via their mobile devices without having to worry about cables. Scenarios include: small buisnesses where everyone's lap tops are connected the minute they walk through the door so they can move around from office to meeting room and stay on the network throughout; hospital nurses carrying out foetal scans without the need for the scanning device to be connected to the screen; construction sites where the technical foreman can log onto the same system as the architect and compare plans on their respective lap tops. At the moment there are various different technologies, all of which suit different scenarios. Many books discuss wLANs in concept, but do not cover the different technologies, or demonstrate how to build a wLAN with only one of the technologies. This book is unique in presenting the broader picture and providing decision makers with the tools they need to make the appropriate investment for their own situation.
* The only book that gives a broad overview of all the different technologies
* Discusses which technologies are best for different situations and requirements along with business trade-offs
* Gives practical hints and advice on how to implement the technologies
* Includes a chapter on the practical details of operating an IEEE802.11b-wLAN together with application examples
* Covers security considerations

Spis treści

Preface xi

Structure of the book xii

1 Introduction 1

1.1 Definition and restriction 1

1.2 Overview of advantages and disadvantages 1

1.3 Applications overview 3

1.4 Market events 6

1.5 Organizations and governing bodies 12

2 Basics 17

2.1 History of wireless vs. wired 17

2.2 Technical communication models and classification 20

2.3 Demands on transfer networks 26

2.4 Properties of electromagnetic waves 28

2.5 Digital modulation technology 33

2.6 Channel access 38

2.7 Spread spectrum techniques 39

2.8 Orthogonal frequency division multiplex procedure 43

2.9 Antennae

2.10 Special features of wireless networks 47

2.11 Frequency allocations 48

3 Applications, devices and standards 51

3.1 Application scenarios 51

3.2 Device types 53

3.3 Standards 54

4 IEEE802.11 57

4.1 The standard 57

4.2 Architectures 59

4.3 Channel access 61

4.4 The Physical layer and bit transfer 81

4.5 Other services 86

4.6 Security 86

4.7 Extensions to the standard 88

5 Bluetooth 95

5.1 The standard 95

5.2 Architectures 99

5.3 Channel access 99

5.4 Controlling states 104

5.5 Bit transfer 108

5.6 Security 110

5.7 System implementation 110

6 DECT 113

6.1 The standard 113

6.2 Architectures 113

6.3 Channel access 114

6.4 Bit transfer 115

6.5 Application profiles 115

7 HomeRF 117

7.1 The standard 117

7.2 Architectures 117

7.3 Channel access 119

7.4 Bit transfer 121

8 HiperLAN/2 123

8.1 The standard 123

8.2 Architectures 125

8.3 Channel access 127

8.4 Bit transfer 130

8.5 Other services 132

8.6 The HiperLAN/2 standard versus IEEE802.1 a 132

9 Operating an IEEE802.11b–complaint WLAN 133

9.1 Introduction 133

9.2 Mobile stations 133

9.3 Access points 136

9.4 Extended networks 141

9.5 Network analysis 143

9.6 Examples from real life 148

10 Various aspects of WLAN technology 153

10.1 Security

10.2 Sources of interference 161

10.3 Selecting a spread spectrum technique 163

10.4 Aspects of EMT interference 165

10.5 WLANs and TCP/IP 167

10.6 Deciding factors 167

10.7 Future prospects 169

Appendix 171

A.1 Maxwellian equations 171

A.2 Physical basis of direct sequence spread spectrum process 171

A.3 Directional antennae 174

B Bibliography 179

B.1 English–language publications 179

B.2 German–language publications 182

C Abbreviations 185

O autorze

Axel Sikora leitet die Fachrichtung Informationstechnik und das Steinbeis-Transferzentrum für Embedded Design und Networking an der Berufsakademie Lörrach.

Blurb

Increasingly, people, computers and microelectronic devices are being linked together to bring to life the communications mantra: anybody, anything, anytime, anywhere. Wireless Personal and Local Area Networks are an essential part of the complex puzzle that will solve the problem of ultimate connectivity.

Understanding wireless Personal and Local Area Networks (WPANs and WLANs) is, in itself, a problem – due to the fact that there are many technologies and products available, the market has not yet been consolidated, and progress and technological innovation is non–stop. The aim of this book is to act as a solid foundation of introductory facts about the technologies upon which the reader can build his/her knowledge of the various networks and systems. The author places special emphasis on explaining the differences between the various WLAN and WPAN technologies.

Features:
∗ State–of–the–art introductions to technology standards: IEEE802.11, Bluetooth, DECT, HomeRF, HiperLAN/2

∗ In–depth discussion on essential aspects of safety, security and compatibility

∗ Practical overview of the structure and administration of a WLAN network along with a sample installation

∗ Criteria for choosing the right WLAN product for your requirements
Network and systems administrators, planners, and designers as well as wireless application developers will find this overview a useful reference, as will small–business managers considering implementing a WPAN or WLAN.