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| Preface | |
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| The Promise of IP Telephony | |
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| The Costs of Telephony | |
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| Reduced Long-Distance Costs | |
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| More Calls with Less Bandwidth | |
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| More and Better Enhanced Services | |
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| Most Efficient Use of IP | |
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| Related Issues | |
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| International Calling | |
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| Telemarketing | |
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| Call Centers | |
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| The Strange Case of the Fax | |
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| The Lure of IP Telephony | |
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| Global Economy, Global Internet | |
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| The Rise of the PC | |
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| The Rise of the World Wide Web | |
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| Early Integration Efforts: ISDN and B-ISDN | |
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| A Model for IP Telephony | |
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| Technical, Economic, and Social Factors | |
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| Regulation | |
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| Digital Voice Fundamentals | |
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| Analog Voice and Digital Data | |
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| The Analog Telephone Network | |
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| Digital Computer Networks | |
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| Analog Links and Digital Links | |
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| The Modem | |
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| The Codec | |
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| The CSU/DSU | |
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| Putting It All Together | |
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| Why Digitize Voice? | |
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| Multiplexing Is Easier | |
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| Signaling Is Easier | |
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| PCs and Other Computers Can Be Used | |
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| The Voice Switch Becomes a Big Computer, and All Lines Are Digital | |
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| Lines Are Not as Noisy | |
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| Line Quality Can Be Monitored Closely | |
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| New Services Can Be Provided | |
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| Lines Are More Tolerant of Noise | |
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| Encryption Is Possible | |
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| The Digital Signal Processor | |
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| Three Steps to Digits: Sample, Quantize, and Code | |
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| Sampling | |
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| Quantizing | |
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| Coding | |
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| A Basic System: 64-kb/s PCM Voice | |
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| Breaking the 64-kb/s Barrier | |
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| Removing Redundancies | |
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| Predicting Voice | |
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| A Note on Voice Quality | |
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| A Sampling of Methods and Standards | |
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| Telephony for IP People | |
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| The Global Telephone Network | |
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| Lines, Trunks, and Switches | |
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| Circuit Switching with Guaranteed Bandwidth and Stable Delays | |
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| Analog Multiplexing | |
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| Digital Multiplexing | |
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| Loops and Trunks: Two-Wire and Four-Wire | |
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| Making Telephone Connections | |
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| Telephone Numbers: The PSTN Network Address | |
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| Electronic Switching and Routing | |
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| Signaling: The Connectionless PSTN | |
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| The Bell System | |
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| The Independents | |
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| ATandT: The Nation's Telephone Company | |
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| The Breakup of the Bell System | |
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| What the Airlines Wrought | |
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| LATAs and Access Charges | |
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| Postdivestiture PSTN | |
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| TA96 | |
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| ILECs, CLECs, and ISPs | |
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| Packet Voice Fundamentals | |
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| Circuit Switching and Packet Switching | |
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| Switching with Circuits | |
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| Switching with Packets | |
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| X.25 Packet Switching | |
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| SS7 as a Connectionless Packet-Switched Network | |
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| The Internet as a Connectionless Packet-Switched Network | |
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| Packetizing Voice | |
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| Small Packets | |
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| Priorities | |
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| Jitter Buffers | |
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| Voice Compression | |
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| Silence Suppression | |
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| Comfort Noise | |
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| RTP | |
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| ISDN: What It Did Not Do | |
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| G. 729B: How to Packetize Voice | |
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| Packets for Telephony People | |
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| Connections and Circuits | |
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| Virtual Circuits | |
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| Establishing Virtual Circuits | |
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| Connectionless Networking | |
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| Switching versus Routing | |
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| The X.25 Network Service | |
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| Enter the Internet | |
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| The Internet Protocol Suite (TCP/IP) Architecture | |
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| The World Wide Web | |
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| Web Graphics | |
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| Web Animation | |
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| User Interaction | |
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| Audio and Video | |
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| An Internet for Voice? | |
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| Voice-Enabled Web Sites | |
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| Why Voice-Enable the Web? | |
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| You Call Us | |
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| We Call You | |
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| We Have VoIP | |
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| Calling Tech Support... | |
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| Can I Get That in Red? | |
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| Call Centers and the Web | |
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| Levels of Call Center Integration | |
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| Inbound Call Centers | |
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| Outbound Call Centers: Telemarketing | |
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| A Distributed VoIP Call Center | |
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| The Internet Watch Company | |
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| Voice-Enabled Web Site Issues | |
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| Standards for IP Telephony | |
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| Following an IP Telephony Call | |
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| The H.323 Framework | |
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| H.323 Architecture | |
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| H.323 for IP Telephony | |
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| Other Application Layer Issues | |
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| Gatekeepers | |
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| H.225 and H.245 | |
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| Multipoint Controllers and Processors | |
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| Session Initialization Protocol | |
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| Addressing and Naming | |
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| Directory Services | |
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| Network Requirements | |
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| RTP and RTCP | |
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| Quality of Service | |
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| Intserv and RSVP | |
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| Diffserv and the ToS Octet | |
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| QoS under IPv6 | |
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| IP Telephony Gateways | |
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| Gateways and Their Attendants | |
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| Destination Lookup | |
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| IP Connection Management | |
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| Compression/Digitization | |
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| IP Packetization and Transport | |
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| Advanced IP/PSTN Signaling | |
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| Authorization, Access, and Accounting | |
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| Necessary Functions | |
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| Are Gateways Always Necessary? | |
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| Gateway Architectures | |
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| PC Platform Gateways | |
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| Router Gateways | |
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| Remote-Access Server Gateways | |
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| PBX VolP Cards | |
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| IP Telephony Switches | |
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| Gateway Components and Features | |
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| Digital Signal Processors | |
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| Physical Ports | |
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| Interface and Hardware Slots | |
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| Means of Configuration | |
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| Reporting System | |
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| Operating System | |
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| Standard Protocol Support | |
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| QoS Support | |
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| Security | |
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| Gatekeepers | |
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| LAN Telephony | |
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| Convergence of the Local Area | |
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| Office Telephony Environments | |
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| LAN Telephony Components | |
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| A Local-Area Network | |
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| LAN Telephony Phones | |
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| Gatekeeper or Call Manager | |
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| PSTN Access Devices | |
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| Benefits of LAN Telephony | |
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| Simplified Adds and Changes | |
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| Multimedia Terminal Capability | |
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| Computer-Telephony Integration | |
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| Challenges and Future of LAN Telephony | |
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| Internet Fax | |
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| Why Fax Persists | |
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| Why Fax Must Change | |
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| How Fax Technology Works | |
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| Call Establishment | |
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| Premessage Procedure | |
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| Message Transmission | |
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| Postmessage Procedure | |
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| Call Release | |
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| Internet Fax Standards | |
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| IETF Fax Efforts | |
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| VolP and FolP | |
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| Architectures for Internet Fax | |
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| PSTN Interface | |
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| Fax Modem | |
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| Fax Protocol Drivers | |
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| Fax Network Drivers | |
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| Packet Network (IP) Protocol | |
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| Internet Fax Product Models | |
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| Fax Servers | |
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| IP-Enabled Fax Machines | |
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| Dedicated IP Fax Gateways | |
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| Integrated VolP/FolP Gateways | |
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| IP Fax Service Providers | |
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| The Future of IP Fax | |
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| International Internet Bypass | |
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| The International Telephony Environment | |
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| Should Anyone Pay for IP Telephony? | |
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| How Should You Pay for IP Telephone Calls? | |
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| International Carriers and the Internet | |
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| Separations, Access Charges, and Settlements | |
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| ATandT Long Lines and Separations | |
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| The MFJ, LATAs, and Access Charges | |
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| International Carriers and Settlements | |
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| Mixing Politics and Technology | |
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| IP Telephony Settlements | |
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| IP Tele-phony? | |
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| Quality of Service in Voice over IP | |
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| Just What Is Quality of Service? | |
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| Granularity | |
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| Performance Guarantees | |
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| Service-Level Agreements | |
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| The QoS Parameters | |
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| Bandwidth | |
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| Delay | |
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| Jitter (Delay Variation) | |
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| Information Loss (Error Effects) | |
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| Availability (Reliability) | |
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| Security | |
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| The Key Role of Bandwidth | |
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| Adding QoS to a Network | |
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| Build It In or Add It On? | |
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| VolP Router Concerns | |
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| Adding QoS to IP | |
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| IP Telephony Case Studies | |
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| Gaba and Sweeney Engineering | |
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| Helena Fabrics | |
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| CCK Networks | |
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| The Future of Voice over IP and Internet Telephony | |
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| The User Future | |
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| Typical Package | |
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| 1-kb/s Packet Voice | |
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| The TelePC and the Ethernet Phone | |
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| Touch, Talk, See | |
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| The Service Provider Future | |
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| Possible Futures | |
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| Service Scenarios | |
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| Technology Scenarios | |
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| How IP on Photons Would Differ from Wireless IP | |
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| Does the PSTN Fade Away? | |
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| Abbreviations and Acronyms | |
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| Index | |