Tài liệu Introduction to Telecommunications Network Engineering - Kỹ thuật viễn thông mạng doc

Introduction to Telecommunications Network Engineering Second Edition Tarmo Anttalainen Artech House Boston • London www.artechhouse.com Contents Preface xv Acknowledgments xix 1 Introduction to Telecommunications 1 1.1 What Is Telecommunications? 1 1.2 Significance of Telecommunications 1 1.3 Historical Perspective 3 1.4 Standardization 7 1.5 Standards Organizations 9 1.5.1 Interested Parties 10 1.5.2 National Standardization Authorities 11 1.5.3 European Organizations 11 1.5.4 American Organizations 12 1.5.5 Global Organizations 13 1.5.6 Other Organizations 14 1.6 Development of the Telecommunications Business 15 v 1.7 Problems and Review Questions 17 References 17 2 The Telecommunications Network: An Overview 19 2.1 Basic Telecommunications Network 19 2.1.1 Transmission 20 2.1.2 Switching 20 2.1.3 Signaling 21 2.2 Operation of a Conventional Telephone 22 2.2.1 Microphone 22 2.2.2 Earphone 23 2.2.3 Signaling Functions 23 2.3 Signaling to the Exchange from the Telephone 24 2.3.1 Setup and Release of a Call 24 2.3.2 Rotary Dialing 25 2.3.3 Tone Dialing 26 2.3.4 Local Loop and 2W/4W Circuits 28 2.5 Telephone Numbering 30 2.5.1 International Prefix 31 2.5.2 Country Code 31 2.5.3 Trunk Code, Trunk Prefix, or Area Code 32 2.5.4 Subscriber Number 32 2.5.5 Operator Numbers 32 2.6 Switching and Signaling 33 2.6.1 Telephone Exchange 33 2.6.2 Signaling 34 2.6.3 Switching Hierarchy 37 2.6.4 Telephone Call Routing 38 2.7 Local-Access Network 41 2.7.1 Local Exchange 42 2.7.2 Distribution Frames 43 2.8 Trunk Network 45 vi Introduction to Telecommunications Network Engineering 2.9 International Network 46 2.10 Telecommunications Networks 47 2.10.1 Public Networks 47 2.10.2 Private or Dedicated Networks 51 2.10.3 Virtual Private Networks 52 2.10.4 INs 53 2.10.5 Public Switched Telecommunications Network Today 56 2.11 Network Management 58 2.11.1 Introduction 59 2.11.2 Who Manages Networks? 59 2.11.3 DCN 61 2.11.4 TMN 62 2.12 Traffic Engineering 65 2.12.1 Grade of Service 65 2.12.2 Busy Hour 66 2.12.3 Traffic Intensity and the Erlang 67 2.12.4 Probability of Blocking 67 2.13 Problems and Review Questions 72 References 75 3 Signals Carried over the Network 77 3.1 Types of Information and Their Requirements 77 3.2 Simplex, Half-Duplex, and Full-Duplex Communication 80 3.3 Frequency and Bandwidth 81 3.3.1 Frequency 82 3.3.2 Bandwidth 83 3.4 Analog and Digital Signals and Systems 85 3.4.1 Analog and Digital Signals 85 3.4.2 Advantages of Digital Technology 86 3.4.3 Examples of Messages 88 Contents vii 3.5 Analog Signals over Digital Networks 91 3.6 PCM 92 3.6.1 Sampling 92 3.6.2 Quantizing 96 3.6.3 Quantizing Noise 97 3.6.4 Nonuniform Quantizing 99 3.6.5 Companding Algorithms and Performance 101 3.6.6 Binary Coding 103 3.6.7 PCM Encoder and Decoder 105 3.7 Other Speech-Coding Methods 106 3.7.1 Adaptive PCM (APCM) 108 3.7.2 Differential PCM (DPCM) 108 3.7.3 DM 109 3.7.4 Adaptive DPCM (ADPCM) 110 3.7.5 Speech Coding of GSM 112 3.7.6 Summary of Speech-Coding Methods 113 3.8 Power Levels of Signals and Decibels 115 3.8.1 Decibel, Gain, and Loss 115 3.8.2 Power Levels 116 3.8.3 Digital Milliwatt 118 3.9 Problems and Review Questions 119 References 124 4 Transmission 125 4.1 Basic Concept of a Transmission System 125 4.1.1 Elements of a Transmission System 125 4.1.2 Signals and Spectra 127 4.2 Radio Transmission 129 4.2.1 CW Modulation Methods 129 4.2.2 AM 129 4.2.3 FM 133 4.2.4 PM 135 4.2.5 Allocation of the Electromagnetic Spectrum 138 viii Introduction to Telecommunications Network Engineering 4.2.6 Free-Space Loss of Radio Waves 141 4.2.7 Antennas 143 4.3 Maximum Data Rate of a Transmission Channel 144 4.3.1 Symbol Rate (Baud Rate) and Bandwidth 144 4.3.2 Symbol Rate and Bit Rate 146 4.3.3 Maximum Capacity of a Transmission Channel 148 4.4 Coding 151 4.4.1 Purpose of Line Coding 152 4.4.2 Spectrum of Common Line Codes 153 4.5 Regeneration 155 4.6 Multiplexing 158 4.6.1 Frequency-Division Multiplexing (FDM) and TDM 158 4.6.2 PCM Frame Structure 159 4.6.3 Plesiochronous Transmission Hierarchy 164 4.6.4 SDH and SONET 166 4.7 Transmission Media 170 4.7.1 Copper Cables 170 4.7.2 Optical Fiber Cables 172 4.7.3 Radio Transmission 175 4.7.4 Satellite Transmission 175 4.8 Transmission Equipment in the Network 176 4.8.1 Modems 177 4.8.2 Terminal Multiplexers 177 4.8.3 Add/Drop Multiplexers 177 4.8.4 Digital Cross-Connect Systems 178 4.8.5 Regenerators or Intermediate Repeaters 178 4.8.6 Optical Line Systems 178 4.8.7 WDM 179 4.8.8 Optical Amplifiers 181 4.8.9 Microwave Relay Systems 182 4.9 Problems and Review Questions 183 References 187 Contents ix 5 Mobile Communications 189 5.1 Cellular Radio Principles 190 5.2 Structure of a Cellular Network 191 5.2.1 Cellular Structure 191 5.2.2 HLR and VLR 192 5.2.3 Radio Channels 193 5.3 Operating Principle of a Cellular Network 194 5.3.1 MS in Idle Mode 194 5.3.2 Outgoing Call 195 5.3.3 Incoming Call 196 5.3.4 Handover or Handoff 196 5.3.5 MS Transmitting Power 196 5.4 Mobile Communication Systems 197 5.4.1 Cordless Telephones 197 5.4.2 PMR (Professional or Private Mobile Radio) 198 5.4.3 Radio Paging 202 5.4.4 Analog Cellular Systems 203 5.4.5 Digital Second Generation Cellular Systems 203 5.4.6 Third Generation Cellular Systems 208 5.4.7 Mobile Satellite Systems 209 5.4.8 WLANs 210 5.4.9 Bluetooth 211 5.5 GSM 212 5.5.1 Structure of the GSM Network 212 5.5.2 Physical Channels 217 5.5.3 Logical Channels 218 5.6 Operation of the GSM Network 219 5.6.1 Location Update 219 5.6.2 Mobile Call 221 5.6.3 Handover or Handoff 223 5.6.4 GSM Security Functions 225 5.6.5 GSM Enhanced Data Services 227 x Introduction to Telecommunications Network Engineering 5.7 GPRS 228 5.7.1 GPRS Network Structure 229 5.7.2 GPRS Network Elements 230 5.7.3 Operation of GPRS 232 5.8 Problems and Review Questions 233 References 235 6 Data Communications 237 6.1 Principles of Data Communications 237 6.1.1 Computer Communications 238 6.1.2 Serial and Parallel Data Communications 238 6.1.3 Asynchronous and Synchronous Data Transmission 239 6.2 Circuit and Packet Switching 242 6.2.1 Circuit Switching 243 6.2.2 Packet Switching 243 6.2.3 Layer 3 Routing and Routers 245 6.2.4 Switching and Routing Through Virtual Circuits 245 6.2.5 Polling 246 6.3 Data Communication Protocols 248 6.3.1 Protocol Hierarchies 248 6.3.2 Purpose and Value of Layering 250 6.3.3 Open Systems Interconnection (OSI) 251 6.3.4 TCP/IP Protocol Stack 260 6.3.5 Data Flow Through a Protocol Stack 260 6.4 Access Methods 262 6.4.1 Voice-Band Modems 262 6.4.2 ISDN 268 6.4.3 DSL 269 6.4.4 Cable TV Networks 277 6.4.5 Wireless Access 279 6.4.6 Fiber Cable Access 280 6.4.7 Leased Lines and WANs 280 6.5 LANs 281 Contents xi 6.5.1 LAN Technologies and Network Topologies 282 6.5.2 Multiple-Access Scheme of the Ethernet 284 6.5.3 CSMA/CD Network Structure 284 6.5.4 Frame Structure of the Ethernet 285 6.5.5 CSMA/CD Collision Detection 288 6.5.6 Twisted-Pair Ethernet 292 6.5.7 Switched Ethernet Switches and Bridges 294 6.5.8 Fast Ethernet 296 6.5.9 Autonegotiation 297 6.5.10 Gigabit Ethernet 298 6.5.11 Upgrade Path of the Ethernet Network 299 6.5.12 Virtual LAN 300 6.6 The Internet 301 6.6.1 Development of the Internet 301 6.6.2 Protocols Used in the Internet 302 6.6.3 Bearer Network Protocols for IP 305 6.6.4 Internet Protocol 306 6.6.5 Address Resolution Protocol 315 6.6.6 Routing Protocols 316 6.6.7 ICMP 317 6.6.8 Structure of Internet and IP Routing 318 6.6.9 Host-to-Host Protocols 319 6.6.10 Application Layer Protocols 327 6.6.11 WWW 331 6.6.12 Voice over IP (VoIP) 337 6.6.13 Summary 341 6.7 Frame Relay 342 6.8 ATM 342 6.8.1 Protocol Layers of ATM 343 6.8.2 Cell Structure of ATM 344 6.8.3 Physical Layer of ATM 346 6.8.4 Switching of ATM Cells 347 6.8.5 Service Classes and Adaptation Layer 348 xii Introduction to Telecommunications Network Engineering 6.8.6 Applications and Future of ATM 350 6.9 Problems and Review Questions 350 References 355 7 Future Developments in Telecommunications 357 7.1 Information Networks 357 7.2 Telephone Services 358 7.3 Wireless Communications 358 7.4 Optical Technology 359 7.5 Digital Broadcast Systems 359 7.6 Summary 360 About the Author 361 Index 363 Contents xiii [...]... capability to transmit voice in addition to data, presents a new challenge to the public telecommunications network operators Wideband access to Introduction to Telecommunications 17 homes will be used for telephone calls in addition to Internet surfing This requires telecommunications network operators, including cellular network operators, to change their strategies from telephone and data transmission to. .. (CCIR/ITU-R) is presently known as ITU-R, where the “R” stands for radio 14 Introduction to Telecommunications Network Engineering ITU-T (CCITT) ISO/IEC ITU-R (CCIR) Figure 1.7 Global standards organizations ITU-T and ITU-R publish recommendations that are in fact strong standards for telecommunications networks ITU-T works for the standards of public telecommunications networks (e.g., ISDN), and ITU-R... last topic of this chapter is an introduction to the theory of traffic engineering; that is, how much capacity we should build into the network in order to provide a sufficient grade of service for the customers 2.1 Basic Telecommunications Network The basic purpose of a telecommunications network is to transmit user information in any form to another user of the network These users of public networks,... new manufacturer to start to produce compatible competing systems Open competition makes products more cost-effective, therefore providing low-cost services to telecommunications users 8 Introduction to Telecommunications Network Engineering Standards increase the market for products adhering to the standard, which leads to mass production and economies of scale in manufacturing and engineering, very... for example, a telephone network, are called subscribers User 19 20 Introduction to Telecommunications Network Engineering information may take many forms, such as voice or data, and subscribers may use different access network technologies to access the network, for example, fixed or cellular telephones We will see that the telecommunications network consists of many different networks providing different... global telecommunications network will evolve toward a common packet-switched network platform for all types of services 1.4 Standardization Communication networks are designed to serve a wide variety of users who are using equipment from many different vendors To design and build networks effectively, standards are necessary to achieve interoperability, compatibility, and required performance in a cost-effective... interconnected into a continuously changing and extremely complicated global system We look at telecommunications from different points of view in order to understand 1 2 Introduction to Telecommunications Network Engineering Mobile telephone Telephone Electrical Data networks Bidirectional Telex Telegraph l ica an ch Me Post Telecommunications Unidirectional mass communication Press Dedicated networks Cable... possibilities available today The business of telecommunications has been growing rapidly, and many newcomers have found employment in this area Even if these xv xvi Introduction to Telecommunications Network Engineering newcomers have a technical background, they may feel that they have a very restricted overall view of the telecommunications network as a whole The first purpose of this book is to provide an... advantages of global telecommunications standards? Problem 1.4 Why is it often difficult to achieve a common understanding of and approve global standards? Explain both political and business interests References [1] Carlson, A B., Communication Systems: An Introduction to Signals and Noise in Electrical Communication, New York: McGraw-Hill, 1986 18 Introduction to Telecommunications Network Engineering [2]... are responsible for developing European-wide standards to ANSI BSI DIN SFS Figure 1.4 Some examples of national standardization authorities 12 Introduction to Telecommunications Network Engineering ETSI CEPT CEN/ CENELEC Figure 1.5 European standards organizations open national borders in order and improve pan-European telecommunications services The European Telecommunications Standards Institute . 2.7 Local-Access Network 41 2.7.1 Local Exchange 42 2.7.2 Distribution Frames 43 2.8 Trunk Network 45 vi Introduction to Telecommunications Network Engineering. Data Services 227 x Introduction to Telecommunications Network Engineering 5.7 GPRS 228 5.7.1 GPRS Network Structure 229 5.7.2 GPRS Network Elements 230