Table of Contents
I. INTRODUCTION TO NETWORKED MULTIMEDIA.
1. An Introduction To RTP.
A Brief History of Audio/Video Networking.
Early Packet Voice and Video Experiments.
Audio and Video on the Internet.
A Snapshot of RTP.
Overview of an RTP Implementation.
Behavior of an RTP Sender.
Behavior of an RTP Receiver.
2. Voice And Video Communication Over Packet Networks.
TCP/IP and the OSI Reference Model.
Performance Characteristics of an IP Network.
Measuring IP Network Performance.
Average Packet Loss.
Packet Loss Patterns.
Network Transit Time.
Acceptable Packet Sizes.
Effects of Multicast.
Effects of Network Technologies.
Conclusions about Measured Characteristics.
Effects of Transport Protocols.
Requirements for Audio/Video Transport in Packet Networks.
Benefits of Packet-Based Audio/Video.
II. MEDIA TRANSPORT USING RTP.
3. The Real-Time Transport Protocol.
Fundamental Design Philosophies of RTP.
The End-to-End Principle.
Standard Elements of RTP.
The RTP Specification.
RTP Payload Formats.
Call Setup and Control.
Quality of Service.
Future Standards Development.
4. RTP Data Transfer Protocol.
The RTP Data Transfer Packet.
Translators and Mixers.
5. RTP Control Protocol.
Components of RTCP.
Transport of RTCP Packets.
RTCP Packet Formats.
RTCP RR: Receiver Reports.
RTCP SR: Sender Reports.
RTCP SDES: Source Description.
RTCP BYE: Membership Control.
RTCP APP: Application-Defined RTCP Packets.
Security and Privacy.
Basic Transmission Rules.
Comments on Reconsideration.
Common Implementation Problems.
6. Media Capture, Playout, And Timing.
Behavior of a Sender.
Media Capture and Compression.
Audio Capture and Compression.
Video Capture and Compression.
Use of Prerecorded Content.
Generating RTP Packets.
Timestamps and the RTP Timing Model.
Payload Format-Specific Headers.
Behavior of a Receiver.
Receiving Data Packets.
Receiving Control Packets.
The Playout Buffer.
Playout Time Calculation.
Adapting the Playout Point.
Playout Adaptation for Audio with Silence Suppression.
Playout Adaptation for Audio without Silence Suppression.
Playout Adaptation for Video.
Decoding, Mixing, and Playout.
7. Lip Synchronization.
8. Error Concealment.
Techniques for Audio Loss Concealment.
Measuring Audio Quality.
Other Techniques for Repairing Speech Signals.
Techniques for Video Loss Concealment.
Other Techniques for Repairing Video.
9. Error Correction.
Forward Error Correction.
Unequal Error Protection.
Audio Redundancy Coding.
Reference Picture Selection.
RTCP as a Framework for Retransmission.
At a Receiver.
At the Sender.
10. Congestion Control.
The Need for Congestion Control.
Congestion Control on the Internet.
Implications for Multimedia.
Congestion Control for Multimedia.
TCP-Like Rate Control.
TCP-Friendly Rate Control.
IV. ADVANCED TOPICS.
11. Header Compression.
Patterns, Robustness, and Local Implementation.
Operation of CRTP: Initialization and Context.
Operation of CRTP: Compression and Decompression.
Effects of Packet Loss.
Robust Header Compression.
Operation of ROHC: States and Modes.
Considerations for RTP Applications.
12. Multiplexing And Tunneling.
The Motivation for Multiplexing.
Tunneling Multiplexed Compressed RTP.
Basic Concepts of TCRTP.
Other Approaches to Multiplexing.
13. Security Considerations.
Confidentiality Features in the RTP Specification.
Confidentiality Using the Secure RTP Profile.
Confidentiality Using IP Security.
Authentication Using Standard RTP.
Authentication Using the Secure RTP Profile.
Authentication Using IP Security.
Denial of Service.
Mixers and Translators.
IETF RFC Standards.
Conference and Journal Papers.
The Real-time Transport Protocol (RTP) provides a framework for delivery of audio and video across IP networks with unprecedented quality and reliability. In RTP: Audio and Video for the Internet, Colin Perkins, a leader of the RTP standardization process in the IETF, offers readers detailed technical guidance for designing, implementing, and managing any RTP-based system.
By bringing together crucial information that was previously scattered or difficult to find, Perkins has created an incredible resource that enables professionals to leverage RTP's benefits in a wide range of Voice-over IP (VoIP) and streaming media applications. He demonstrates how RTP supports audio/video transmission in IP networks, and shares strategies for maximizing performance, robustness, security, and privacy.
Comprehensive, exceptionally clear, and replete with examples, this book is the definitive RTP reference for every audio/video application designer, developer, researcher, and administrator.
Key coverage includes: RTP's goals, design philosophy, and relationships with other protocols The psychology of human perception in the design of media delivery systems RTP data transfer and control protocols, including framing, loss detection, reception quality feedback, and membership controlMedia playout, timing, and synchronization, including lip synchronization Mitigating network problems: error concealment, error correction, and congestion controlOptimizing performance over low-speed links: header compression, multiplexing, and tunnelingIntegrating leading media codecs and standards into RTP systems Securing RTP sessions: encryption, authentication, and the new secure RTP profile for wireless networksExtensive references and practical examples throughout
Colin Perkins is a research assistant professor at the University of Southern California Information Sciences Institute, where his research interests include scaling Internet multimedia conferencing to support very large distributed meetings and to very high quality. From 1996 to 2000, he was a research fellow with the Department of Computer Science, University College, London, where he conducted research into advanced VoIP and IP-based videoconferencing technologies, and developed one of the earliest RTP teleconferencing implementations. He is co-chair of the Audio/Video Transport and Multiparty Multimedia Session Control working groups of the IETF, and has authored several RFC standards relating to RTP. He holds a Ph.D. in electronic engineering from the University of York.