Voice over IP Fundamentals
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Library of Congress Cataloging-in-Publication Number: 99-61716
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Dedications
Jonathan Davidson:
Wife, Daughter, Son
To my beautiful wife Shelly for putting up with me during the nights and weekends
spent working on this book. A better wife, mother, and friend could not be asked for.
To my daughter Megan, who will probably be learning data and voice networking in
high school by the time she gets there. Also, my son Ethan, who will probably think
that video and audio conferencing is as common as videogames and VCRs were to
my generation.
James Peters:
To my son Justin, for his curiousity, friendship, and the bond that we share.
To my son Zachary, who has taught me to laugh and to not take life so seriously.
To my daughter Breanna, whose smile makes me realize how beautiful life is.
Voice over IP Fundamentals
Feedback Information
Acknowledgments
Introduction
Purpose of This Book
Audience
Chapter Organization
Features and Text Conventions
Timeliness
The Road Ahead…
I: PSTN
1. Overview of the PSTN and Comparisons to Voice over IP
The Beginning of the PSTN
Understanding PSTN Basics
PSTN Services and Applications
Drivers Behind the Convergence Between Voice and Data Networking
Packet Telephony Network Drivers
New PSTN Network Infrastructure Model
Summary
2. Enterprise Telephony Today
Similarities Between PSTN and ET
Differences Between PSTN and ET
Common ET Designs
Summary
3. Basic Telephony Signaling
4
Signaling Overview
E&M Signaling
CAS
ISDN
QSIG
DPNSS
Summary
4. Signaling System 7
SS7 Network Architecture
SS7 Protocol Overview
SS7 Examples
List of SS7 Specifications
Summary
5. PSTN Services
Plain Old Telephone Service
Integrated Services Digital Network
Business Services
Service Provider Services
Summary
II: Voice over IP Technology
6. Voice over IP Benefits and Applications
Key Benefits of VoIP
Packet Telephony Call Centers
Service Provider Calling-Card Case Study
Value-Added Services
Enterprise Case Study: Acme Corporation
Summary
7. IP Tutorial
OSI Reference Model
Internet Protocol
Data Link Layer Addresses
IP Addressing
Routing Protocols
EIGRP
IP Transport Mechanisms
Summary
References
8. VoIP: An In-Depth Analysis
Delay/Latency
Jitter
Pulse Code Modulation
Voice Compression
Echo
Packet Loss
Voice Activity Detection
Digital-to-Analog Conversion
Tandem Encoding
Transport Protocols
Dial-Plan Design
End Office Switch Call-Flow Versus IP Phone Call
Summary
References
9. Quality of Service
5
QoS Network Toolkit
Edge Functions
Traffic Policing
Backbone Networks
Rules of Thumb for QoS
Cisco Labs' QoS Testing
Summary
III: IP Signaling Protocols
10. H.323
H.323 Elements
H.323 Protocol Suite
H.323 Call-Flows
Summary
11. Session Initiation Protocol
SIP Overview
SIP Messages
Basic Operation of SIP
Summary
12. Gateway Control Protocols
Simple Gateway Control Protocol
Media Gateway Control Protocol
Summary
13. Virtual Switch Controller
Overview of the Virtual Switch
Open Packet Telephony
Packet Voice Network Overview
VSC Architecture and Operations
VSC Implementation
Summary
IV: Voice over IP Applied
14. Voice over IP Configuration Issues
Dial-Plan Considerations
Feature Transparency
Cisco's Dial-Plan Implementation
Summary
15. Voice over IP Applications and Services
Enterprise Applications and Benefits
Enterprise VoIP Case Study: B.A.N.C. Financing International
Service Provider Case Study: Prepaid Calling Card
Summary
A. ISUP Messages/ Types Formats
Feedback Information
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