Internet
Communications
Using SIP
Delivering VolP and Multimedia
Services with Session Initiation
Protocol
John Wiley & Sons, Inc.
NEW YORK • CHICHESTER • W E I N H E I M • BRISBANE • SINCAPORE • TORONTOContents
Foreword
Preface
Acknowledgments
Chapter 1 Introduction
Problem: Too Many Networks Network Consolidation
Voice on the Net
SIP Is Not a Miracle Protocol The Short History of SIP References in This Book
References for Telephony References
Chapter 2 IP Communications Enabled by SIP
Internet Multimedia Protocols The Value of Signaling
Addressing SIP Capabilities
Overview of Services Provided by SIP Intelligent Network Services Using SIP: ITU Services CS-1 and CS-2
Presence and Instant Communications
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8 8 9 11 12 13 15X Contents
Service Creation
Mixed Internet-PSTN Services ENUM
SIP Security SIP Orphans
SIP Interworking with ITU-T Protocols What SIP Does Not Do
Overview of SIP Services by Market Segment Commercial SIP Products
More Work Ahead References
Chapter 3 Architectural Principles of the Internet
Telecom Architecture Internet Architecture
The Internet Standards Process
Protocols and Application Programming Interfaces References
Chapter 4 Internet Multimedia and Conferencing
Introduction
Freshening Up on IP
Internet Multimedia Protocols Multicast Protocols
Transport Protocols Internet Services
Media and Data Formats
Multimedia Server Recording/Playback Control Session Description
Session Announcements Session Invitation
Authentication and Key Distribution Summary
References
Chapter 5 SIP Overview
What Makes SIP Special SIP-Enabled Network
Watching How Sausages Are Being Made What SIP Is Not
Introduction to SIP
Elements of a SIP Network SIP Functions Address Resolution Session-Related Functions Non-Session-Related Functions 19 20 21 22 22 23 24 25 27 28 29
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Chapter 6 SIP Service Creation 87
Services in SIP 87 Service Example 88 New Methods and Headers 92
Service Creation Options 93 Call Processing Language 94 SIP Common Gateway Interface 98 SIP Application Programming Interfaces 99
SIP and VoiceXML 100
Summary 101 References 101
Chapter 7 User Preferences 103
Introduction 103 Preferences of Caller 104
Example for Contact 105 Example for Accept-Contact 106
Example for Reject-Contact 106 Preferences of the Called Party 107 Server Support for User Preferences and for Policies 108
Summary 108 References 108
Chapter 8 Security, NATs, and Firewalls 109
Basics of SIP Security 110 Authentication 110 Encryption 111 Digital Signatures 113 Network Address Translators 113
Firewalls 116 ALG, Firewall, and NAT Traversal 117
Privacy Considerations 120 Design of a Secure SIP Network 123
Summary 124 References 124
Chapter 9 SIP-Based Telephony 127
Basic Telephony Services 127 SIP and PSTN Interworking
Gateway Location and Routing 128 Enhanced Telephony Services 137 Call Control Services and Third-Party Call Control 141
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SIP Third-Party Call Control 144
Summary 148 References 149
Chapter 10 Voice Mail and Unified Messaging 151
Problem Statement 151 Example of Unified Message Operation and Architecture 152
RTSP-Enabled Voice Message Retrieval 154
Message-Waiting Notification 154
Summary 159 References 159
Chapter 11 Presence and Instant Communications 161
The Emergence of Instant Messaging 161 The IETF Model for Presence and Instant Messaging 162
Security for Presence and IM 164 The Common Profile for Instant Messaging 165
Presence Service 166 Instant Message Service 167 Why SIP for Presence and Instant Messaging? 167
New Services Based on SIP for Presence 168
Ponte Calüng 168 Avoiding Unsuccessful Calls 169
Automatic Call-Back on Presence 169 Legitimate Tracking of the Workforce 169 Replacing Traditional Telephony Services and Devices 169
Architecture for Instant IP Communications 170
Basic Call Flows for SIP IM 173 SIP for Instant Messaging 174 Lightweight Data Formats 175 Communications Based on Presence 175
References 177
Chapter 12 SIP Conferencing 179
Introduction 179 SIP Conferencing Models 180
Ad Hoc and Scheduled Conferences 183
Summary 185 References 185
Chapter 13 Mixed PSTN and Internet Telephony Services 187
Introduction 187 Click-to-Connect: An Action on the Web Initiates a
Call on the PSTN 188 Internet (Alert for) Call Waiting: An Incoming PSTN
Introduction to PINT 189 PINT Extensions to SDP 190 Examples of PINT Requests and Responses 191
Introduction to SPIRITS 193 Call Flows for Internet Call Waiting 194
IN-SIP Gateway and Services 196 Enhancing or Replacing IN with SIP 198 SPIRITS and INAP Interworking 198
Summary 200 References 200
Chapter 14 DNS and ENUM 201
Introduction: DNS and Directories 201
Addressing and DNS 202 URIs and URLs 202 The Domain Name System 202
DNS and Directory Security 207 DNS-Based Directory Services Using SIP 210
Single Contact Address 211 Three-Level Directory Systems 212
Summary 219 References 219
Chapter 15 SIP Mobility 221
Mobile Networks 221 Dimensions of Mobility 222 Mobility Examples 223 Mobüe IP 223 Roaming Users 225 Remote Registration 225 SIP Precall Mobility 225 SIP Midcall Mobility 229 Personal Mobility 229 SIP Service Mobility 230
Summary 231 References 231
Chapter 16 AAA and QoS for SIP 233
Options to Achieve QoS 233 Separation of Network and Application Signaling 234
Network Models for QoS 235 Single Domain QoS 235 Interdomain QoS 237 The Application Policy Server 239
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QoS Options 241 Summary 244 References 245
Chapter 17 The Component Server Architecture 247
Services for IP Telephony Gateways 247 The Integrated Applications Environment 251 Integration of Web, Email, and Voice 254 Examples of Integrating Component Services 255
CollectingofDTMFDigits 256 Interactive Voice Response 258 Scheduled Conference Service 258
Voice Mail 260 Summary 261 References 261
Chapter 18 Conclusions and Future Directions 265
TheFutureofSIP 265 Future Services 265 Summary 267 References 267 Glossary 269 Index 275
