1. Chapter 1 Voice and Data: Two Separate Worlds?

   1. The PSTN

   2. Key Systems and PBXs

   3. Limits of Traditional Telephony

   4. VoIP in the Home

   5. VoIP in Business

   6. VoIP's Changing Reputation

   7. Key Issues: Voice and Data: Two Separate Worlds

2. Chapter 2 Voice over Data: Many Conversations, One Network

   1. VoIP or IP Telephony

   2. Distributed Versus Mainframe

   3. Key Issues: Voice over Data: Many Conversations, One Network

3. Chapter 3 Linux as a PBX

   1. Free Telephony Software

   2. Installing Legacy Interface Cards

   3. Compiling and Installing Asterisk

   4. Monitoring Asterisk

   5. Key Issues: Linux as a PBX

4. Chapter 4 Circuit-Switched Telephony

   1. Regulation and Organization of the PSTN

   2. Components of the PSTN

   3. Customer Premises Equipment

   4. Time Division Multiplexing

   5. Point-to-Point Trunking

   6. Legacy Endpoints

   7. Dial-Plan and PBX Design

   8. Key Issues: Circuit-Switched Telephony

5. Chapter 5 Enterprise Telephony Applications

   1. Application Terminology

   2. Basic Call Handling

   3. Administrative Applications

   4. Messaging Applications

   5. Advanced Call-Handling Applications

   6. CTI Applications

   7. Key Issues: Telephony Applications

6. Chapter 6 Replacing the Voice Circuit with VoIP

   1. The "Dumb" Transport

   2. Voice Channels

   3. Project 6.1. Set Up Custom Codec Selection and Enable an Independent Call Path

   4. Key Issues: Replacing the Voice Circuit with VoIP

7. Chapter 7 Replacing Call Signaling with VoIP

   1. VoIP Signaling Protocols

   2. H.323

   3. SIP

   4. IAX

   5. MGCP

   6. Cisco SCCP

   7. Heterogeneous Signaling

   8. Key Issues: Replacing Call Signaling with VoIP

8. Chapter 8 VoIP Readiness

   1. Assessing VoIP Readiness

   2. Business Environment

   3. Network Environment

   4. Implementation Plan

   5. Key Issues: VoIP Readiness

9. Chapter 9 Quality of Service

   1. QoS Past and Present

   2. Latency, Packet Loss, and Jitter

   3. CoS

   4. 802.1q VLAN

   5. Quality of Service

   6. Residential QoS

   7. Voice QoS on Windows

   8. Best Practices for Quality of Service

   9. Key Issues: Quality of Service

10. Chapter 10 Security and Monitoring

    1. Security in Traditional Telephony

    2. Security for IP Telephony

    3. Access Control

    4. Software Maintenance and Hardening

    5. Intrusion Prevention and Monitoring

    6. Project 10.3. Logging and Controlling VoIP Packets with iptables

    7. Key Issues: Security and Monitoring

11. Chapter 11 Troubleshooting Tools

    1. VoIP Troubleshooting Tools

    2. The Three Things You'll Troubleshoot

    3. SIP Packet Inspection

    4. Interoperability

    5. Project 11.3. Trace Both Ends of a Call Setup with Log Comparison

    6. When, Not if, You Have Problems...

    7. Simulating Media Loads

    8. Key Issues: Troubleshooting Tools

12. Chapter 12 PSTN Trunks

    1. Dial-Tone Trunks

    2. Routing PSTN Calls at Connect Points

    3. Timing Trunk Transitions

    4. Key Issues: PSTN Trunks

13. Chapter 13 Network Infrastructure for VoIP

    1. Legacy Trunks

    2. VoIP Trunks

    3. Project 13.1 Use Dial-Plan to Connect to Multiple VoIP Networks

    4. WAN Design

    5. Disaster Survivability

    6. Metro-Area Links

    7. Firewall Issues

    8. Peer-by-Peer Codec Selection

    9. Project 13.2. Build an Interactive Directory on a SIP Display Phone

    10. Key Issues: Network Infrastructure for VoIP

14. Chapter 14 Traditional Apps on the Converged Network

    1. Fax and Modems

    2. Fire and Burglary Systems

    3. Surveillance Systems and Videoconferencing

    4. Voice Mail and IVR

    5. Emergency Dispatch/911

    6. Key Issues: Traditional Apps on the Converged Network

15. Chapter 15 What Can Go Wrong?

    1. Common Problem Situations

    2. Key Issues: What Can Go Wrong?

16. Chapter 16 VoIP Vendors and Services

    1. Softphones and Instant Messaging Software

    2. Skype

    3. Other Desktop Telephony Software

    4. Developer Tools and SoftPBX Systems

    5. VoIP Service Providers

    6. Telephony Hardware Vendors

17. Chapter 17 Asterisk Reference

    1. How Asterisk Is Supported

    2. Asterisk's Configuration Files

    3. Asteriskdial-planAsterisk Dial-Plan

    4. AsteriskchannelsAsterisk Channels

    5. The Asterisk CLI

    6. Integrating Asterisk with Other Software

    7. Key Issues: Asterisk Reference

1. Appendix A SIP Methods and Responses

2. Appendix B AGI Commands

3. Appendix C Asterisk Manager Socket API Syntax

4. Glossary

5. Colophon

Our look is the result of reader comments, our own experimentation, and feedback from distribution channels. Distinctive covers complement our distinctive approach to technical topics, breathing personality and life into potentially dry subjects.

The animals on the cover of Switching to VoIP are hyacinth macaws (Anodorhynchus hyacinthinus). The bright blue hyacinth is the largest species of macaw, growing up to 40 inches in length. Surviving in three distinct populations in southern Brazil, eastern Bolivia, and northeastern Paraguay, the hyacinth macaw prefers riverside tropical rain forests and palm swamps. They can be found in pairs or in small groups, males and females looking nearly indistinguishable.

Hyacinths mate for life. The female incubates the eggs, while the male collects and brings food to her. The young stay with their parents for about six months before setting off on their own, but they don't reach maturity and start breeding until they are about seven years old. While the hyacinth lifespan in still uncertain, some scientists think that the birds live up to 60 years.

The hyacinth's diet consists of a large variety of nuts and seeds, many of which would be inaccessible without the bird's exceptionally powerful bill. Part of this diet includes unripe fruit and poisonous seeds that no other animal can digest. Scientists speculate that digesting these toxins is only possible because of another part of the hyacinth's diet-large chunks of moist clay from river banks. This clay helps absorb and neutralize the poisons. In their messy eating habits, hyacinth macaws play an important role in seed dispersal. They seem to carry and drop seeds everywhere they go.

Adam Witwer was the production editor and Norma Emory was the copyeditor for Switching to VoIP. Sada Preisch proofread the text. Matt Hutchinson and Claire Cloutier provided quality control. Peter Ryan provided production assistance. Angela Howard wrote the index.

Ellie Volckhausen designed the cover of this book, based on a series design by Edie Freedman. The cover image is from the Dover Pictorial Archive. Karen Montgomery produced the cover layout with Adobe InDesign CS using Adobe's ITC Garamond font.

David Futato designed the interior layout. This book was converted by Keith Fahlgren to FrameMaker 5.5.6 with a format conversion tool created by Erik Ray, Jason McIntosh, Neil Walls, and Mike Sierra that uses Perl and XML technologies. The text font is Linotype Birka; the heading font is Adobe Myriad Condensed; and the code font is LucasFont's TheSans Mono Condensed. The illustrations that appear in the book were produced by Robert Romano, Jessamyn Read, and Lesley Borash using Macromedia FreeHand MX and Adobe Photoshop CS. The tip and warning icons were drawn by Christopher Bing. This colophon was written by Adam Witwer.