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The Information Technology: Transmission, Processing, and Storage

Series Editor: Jack Keil Wolf University of California at San Diego LaJolla, California

Editorial Board: Robert J. McEliece California Institute of Technology Pasadena, California

John Proakis Northeastern University Boston, Massachusetts

William H. Tranter Virginia Polytechnic Institute and State University Blacksburg, Virginia

Coded Systems John B. Anderson and Ame Svensson

Communication System Design Using DSP Algorithms: With Laboratory Experiments for the TMS320C6701 and TMS320C6711 Steven A. Tretter

Interference Avoidance Methods for Systems Dimitrie C. Popescu and Christopher Rose

MIMO and Systems Horst J. Bessai

Multi-Carrier Digital Communications: Theory and Applications of OFDM Ahmad R.S. Bahai, Burton R. Saltzberg, and Mustafa Ergen

The Multimedia Internet Stephen Weinstein

Performance Analysis and Modeling of Digital Transmission Systems William Turin

Stochastic Image Processing Chee Sun Won and Robert M. Gray

Wireless Communications Systems and Networks Mohsen Guizani

A Continuation Order Plan is available for this series. A continuation order will bring delivery of each new volume immediately upon publication. Volumes are billed only upon actual shipment. For further information please contact the publisher. The Multimedia Internet

Stephen Weinstein Communication Theory and Technology Consultants, Summit, NJ

^ Springer A CLP. Catalogue record for this book is available from the Library of Congress.

ISBN 0-387-23681-3

© 2005 Springer Science+Business , Inc. All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, Inc., 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights.

Printed in the United States of America. (IBT)

987654321 springeronline.com To our grandchildren Andrew, Matthew, Cayenn and Simone. PREFACE and ACKNOWLEDGEMENTS

This book is a light technical introduction to the three technical foundations for multimedia applications across the Internet: communications (principles, technologies and networking), compressive encoding of , and Internet protocols and services. The QoS (Quality of Service) required for audio, image and media comes from communication networks with high capacity and provisions for multiple user access, from the compressive encodings that hold information rates to levels consistent with current storage media and communication networks, and from the packet servicing and media stream control capabilities specified in Internet protocols and services. All of these contributing systems elements are explained in this book through descriptive text and numerous illustrative figures. The result is a book pitched toward non-specialists, preferably with technical background, who want descriptive tutorial introductions to the three foundation areas. Much of the book is accessible to the non-technical reader as well. Some sections are more technical than others and it was my original intention to flag them, but they, too, contain introductory and explanatory materials and I decided to let the reader decide what she or he wants to read, glance at, or skip altogether. The book should be especially useful to individuals active in one or another foundation area, or in industries that rely on electronic media, who are curious about the whole range of Internet-oriented technologies supporting multimedia applications. Those who wish to go beyond the contents here can consult the references, including many Internet RFCs (requests for comments) and useful Web sites. "Multimedia", already a shaky noun as well as an adjective, can be broadly defined as electronically augmented or generated objects and experiences that appeal to the senses. "Media" can be single or multiple in a communication session and should not be confused with transmission media such as , , , and copper wire. There are plenty of electronic media products and services, some long established such as broadcast, cable, satellite ; audio and video recordings; and computer games. There are others relatively new such as retrieval, exchange, and streaming of media objects on the World Wide Web; Internet radio and television; and VoIP (Voice over Internet Protocol) with its generalization into multimedia conferencing. Multimedia has connotations of computer processing and is now firmly rooted in IP internetworking, but there is no clear line dividing current concepts from past examples of electrically-supported yiil The Multimedia Internet sensory experiences. The Multimedia Internet is simply a continuation of the past 125 years of technology development for communications and entertainment, relying now on cheap and powerful computer processing, broadband networking, packet communication using IP, and techniques for media QoS across the Internet. Although QoS capabilities have so far been talked about more than built into the Internet, and some people doubt that IP networks will ever provide the level of QoS associated with circuit-switched networks such as the PSTN (Public Switched Network), multimedia applications are already flourishing on the Internet. They will go much farther as broadband access, wired and wireless, becomes widely available to users wherever they are. This will be encouraged by a proliferation of Internet appliances in which the multimedia Internet is imbedded rather than being consciously utilized. A good example is a wireless Internet radio - hopefully with earphones - able to select from thousands of stations from around the world. Barring further delays from the intellectual property disputes that were a significant impediment at the time of , we may soon see these carried by teenagers around shopping centers, schools, and city streets. Significant advances in digital audio/video encoding, optical and wireless communications technologies, high-speed access networks, and IP-based media streaming have made the multimedia Internet feasible. These technologies, described in this book, are among the most important foundations for the present and near-future Multimedia Internet, but the book does not claim to provide a comprehensive examination of all relevant technologies. A number of important areas are largely or entirely outside the scope of this book, including systems for media program composition and production; media synchronization, storage, and search; user interfaces; "groupware" for collaborations across the Internet; such as virtual reality environments and personalities, gestures, facial expressions, touch, and smell; caching and proxy server techniques; routing protocols; authentication and security systems; and communication coding techniques, network design, traffic engineering, and network management. Despite these omissions, the book answers the question, from the author's personal perspective, of "What are the important technical concepts for delivery of audio/visual and other media through the Internet?" It should meet the needs of most readers in content and technology industries who want to know more about aspects of media delivery outside of their own specialties, and are willing to consult the references for additional technical details. Some notes on notation: -Block diagrams indicate a processing sequence. In the example here, signals a(t) and b(t) enter a processing unit, a "black box" that yields a m(t), which is multiplied by a signal c(t) to generate s(t), to which n(t) is added to yield y(t). Most implementation details of black boxes are left to specialized textbooks.

a(t) m(t),,0 s(t)^. ^ processor b(t)T c(t)T n(t)' -The letter "t" represents time, with typical units of sec, ms (millisecond=10rk-"3 sec), |xs (microsecond=10"^ sec), ns (nanosecond=10'^ sec, and ps (picosecond=10"^^ sec). Preface and Acknowledgements IX

-The letter "f represents frequency, with typical units of Hz (Hertz or cycles/sec), KHz (kiloHertz=10^ Hz), MHz (megaHertz=10^ Hz), and GHz (gigaHertz=10^ Hz). Bandwidth, too, is measured in Hertz, e.g. "the 300Hz-3KHz band". -The Greek letter ">-" represents wavelength, which is convertible to frequency as described in Chapter 3, and comes in typical units of nm (nanometer=10"^ meter). -Data rate is designated in bps (bits per second), kbps, mbps, gbps, and tbps (terabits/sec= 10^^ bps). It may also be expressed in Bps (bytes per second), where a byte is 8 bits. I may forget and use "Kbps" with a capital K. -Computer memory is measured in power of two multiples of Bytes, e.g., KB = 2^^ = 1024 bytes, MB = 2^^ = 1,048,576 bytes, with capital K or B. -Web addresses (URLs) are presented without the http:// prefix, e.g., www.whitehouse.gov. - References are enclosed in brackets. For example, [RFC3550] refers to an entry in the alphabetical reference list. When a Web address is bracketed as a reference, e.g., [www.ieee.org], there is no entry in the Index. Two or more references may be enclosed within the same brackets, e.g., [RFC3550, www.ieee.org]. The contents of the five chapters are briefly summarized below, with most acronyms left for definition in the chapters:

Chapter 1: A BACKGROUND FOR NETWORKED DIGITAL MEDIA Media applications and an overview of basic concepts including protocol layering, client-server and peer- to-peer systems, media computing and devices, media communication, A/D conversion, communication, and QoS.

Chapter!: DIGITAL AUDIO AND VIDEO Digital encoding techniques and systems, in particular lossless and lossy compressive image coding, the discrete cosine transform, JPEG image compression, H.261/263 and MPEG 1, 2 and 4 video, MP-3 and AAC audio coding, wavelet image compression, and HDTV.

Chapter 3: COMMUNICATION TECHNOLOGIES AND NETWORKS Circuit, packet, and cell-switched communication (connection-oriented and connectionless); computer communication; the optical core network; modulation and MIMO (multiple antenna) techniques; and wired and wireless local and access networks (xDSL, cable data, cellular mobile, WiMax, WiFi, switched Ethernet) with attention to medium access control and QoS prioritizations.

Chapter 4: INTERNET FOUNDATIONS History and architecture; IPv4 and IPv6; TCP and UDP transport protocols; HTTP and MIME for the Web; QoS through Service Level Agreements, DiffServ traffic distinctions and MPLS traffic engineering; HTML and XML markup languages.

Chapter 5: MEDIA SYSTEMS AND PROTOCOLS VoIP and H.323 systems; SIP signaling and RSVP reservation protocols; RTP media streaming and RTSP media stream control protocols; implementations of media streaming in the Internet.

I regret that many of the illustrative topics and current standards described in this book will quickly become obsolete in the fast-moving multimedia field. However, the basic concepts that are the core content of the book should have a much longer shelf life, and the more transient material helps explain the current and near-future state of the art. I thank the many colleagues who have commented on sections of this book, especially Shih-Fu Chang, Jerry Hayes, Aleksandar Kolarov, X The Multimedia Internet

Thomas Kuehnel, Joseph Lechleider, Michael Luby, Johannes Peek, Jens-Peter Redlich, Donald Schilling, Mischa Schwartz and Henning Schulzrinne, and take full responsibility for the errors that remain. I appreciate also Syed All's help with my personal computing problems. I am very grateful for the patience, support, and good advice of my wife, Judith and my editor at Springer, Ana Bozacevic, and for the support of Ana's colleague and my friend Alex Greene. It may seem ironic that this book is not a multimedia document, but its subject is the supporting technologies rather than multimedia content or experiences themselves. My hope is that the multimedia Internet will be partly demystified by this book's explanation of how things work.

Stephen Weinstein Summit, New Jersey, December, 2004 CONTENTS

1. A BACKGROUND FOR NETWORKED DIGITAL MEDIA 1 1.1 PROTOCOL LAYERING AND AN INTRODUCTION TO NETWORK ADDRESSES AND PORTS 2 1.2 WHAT IS MULTIMEDIA? 4 1.3 MULTIMEDIA EXCHANGES 6 1.4 CONSUMER-ORIENTED APPLICATIONS 11 1.5 MULTIMEDIA COMPUTING AND DEVICES 20 1.5.1 Digital Video Display Formats 26 1.5.2 Liquid Crystal Display Technology 29 1.5.3 Storage Technologies and Requirements 30 1.6 THE PHYSICAL FUNDAMENTALS: SINUSOIDS, FREQUENCY SPECTRA, AND BANDWIDTH 32 1.6.1 Frequency and Bandwidth-Related Operations 34 1.7 ANALOG TO DIGITAL MEDIA CONVERSION 39 1.7.1 The Sampling Theorem 40 1.7.2 and Pulse Modulation 41 1.7.3 Digitized vs. Synthesized Media 44 1.8 QUALITY OF SERVICE CRITERIA 46

2. DIGITAL CODING OF AUDIO AND VIDEO 51 2.1 THE ALTERNATIVES AND TRADEOFFS OF DIGITAL CODING 53 2.2 LOSSLESS ENTROPY CODING 56 2.2.1 Huffman Coding 56 2.2.2 Arithmetic Coding 57 2.2.3 FLAC (Free Lossless Audio Codec) 59 2.3 THE TIFF, AIFF, and WAV FILE FORMATS 60 2.4 FACSIMILE COMPRESSIVE CODING 63 xii The Multimedia Internet

2.5 TRANSFORM-DOMAIN CODING: THE DISCRETE COSINE TRANSFORM (DCT) 64 2.6 TRANSFORM-DOMAIN CODING: WAVELET DECOMPOSITION 67 2.7 JPEG STILL IMAGE CODING 72 2.8 JPEG 2000 STILL IMAGE CODING 76 2.9 COMPRESSIVE VIDEO CODING 78 2.9.1 Motion JPEG and Digital Video 79 2.9.2 H.261 and H.263 Conferencing Video 81 2.10 MPEG 85 2.10.1 Levels of Containment: I, P and B Frames, the Group of Pictures, and Macroblocks 88 2.10.2 Intra- and Inter-Picture Compressive Coding 89 2.10.3 The MPEG-2 Systems Layer 93 2.10.4 MPEG Audio Coding: MP-3 and AAC 97 2.10.5 MPEG-4 101 2.10.5.1 Scene Description, Data Streams, and Encoding 101 2.10.5.2 MPEG-4 Systems Level 105 2.10.5.3 H.26L 107 2.10.5.4 DivX 110 2.10.6 MPEG-21 110 2.10.7 Digital Television and the :Grand Alliance" HDTV System 113 2.11 MEDIA ENCODING SYSTEMS AND COMMUNICATIONS CAPACITY 119

\. COMMUNICATION NETWORKS AND TECHNOLOGIES 121 3.1 NETWORK CATEGORIES 122 3.2 THE DWDM CORE OPTICAL NETWORK 125 3.2.1 Opaque and Transparent Optical Nets, and Hierarchical Switching 128 3.2.2 SONET and IP Traffic 131 3.3 CIRCUIT, PACKET, AND CELL-SWITCHED COMMUNICATION 134 3.3.1 Circuit-switched Communication 135 3.3.2 Packet-Switched Communication and Routing 136 3.3.3 Asynchronous Transfer Mode 138 3.4 COMPUTER COMMUNICATION FUNDAMENTALS 143 3.5 WIRED LOCAL NETWORKS 147 3.5.1 IEEE 802.3 (Ethernet) 148 3.5.2 IEEE 1394 152 3.6 MODULATION TECHNIQUES 155 3.6.1 Linear Modulation Formats and FM 155 3.6.2 Spread Spectrum: Frequency-hopping, Direct Sequence, and UWB 157 3.6.3 QAM - A Closer Look 160 3.6.4 DMT/OFDM - A Closer Look 162 3.6.5 TrelHs-Coded Modulation and Turbo 167 3.7 WIRED ACCESS NETWORKS 170 Contents ^jlj

3.7.1 xDSL 171 3.7.2 Cable Data Systems 174 3.7.2.1 DOCSIS Medium Access Control 177 3.7.3 Power-Line Access Networking 181 3.8 WIRELESS NETWORKING 182 3.8.1 3G/4G Cellular Mobile Systems 188 3.8.1.1 IEEE 802.20 Mobile Broadband Wireless Access 192 3.8.2 MIMO Antennas and Space-Time Codes 193 3.8.3 IEEE 802.16 Wireless Metropolitan-Area Network "WiMax" 198 3.8.4 IEEE 802.11 "WiFi" 201 3.8.4.1 Modulation in 802.1 la,b,g,n 202 3.8.4.2 MAC for Access and QoS 204 3.8.5 Bluetooth 208 3.8.6 Zigbee/IEEE 802.15.4 210 3.9 THE FUTURE OF BROADBAND COMMUNICATION 211

I. INTERNET PROTOCOLS, SERVICES, AND SOFTWARE 213 4.1 INTERNET HISTORY AND PHYSICAL ARCHITECTURE 215 4.2 BASIC INTERNET SERVICES 220 4.2.1 Multipurpose Internet Mail Extensions (MIME) 221 4.3 THE INTERNET PROTOCOL (IP) 222 4.3.1 IPv4 225 4.3.2 IPv6 228 4.4 TCPANDUDP 231 4.5 ESTTERNET QoS SERVICES 236 4.5.1 Differentiated Services (DiffServ) 237 4.5.1.1 DiffServ Classes and PHB Groups 238 4.5.1.2 The Service Level Specification (SLS) and Traffic Conditioning 240 4.5.2 Integrated Services (IntServ) 244 4.6 MULTI-PROTOCOL LABEL SWITCHING (MPLS) 247 4.7 THE WORLD WIDE WEB 251 4.7.1 The HyperText Transfer Protocol (HTTP) 252 4.8 HYPERMEDIA AND MARKUP LANGUAGES 255 4.8.1 HyperText Markup Language (HTML) 257 4.8.2 extensible Markup Language (XML) 261 4.8.2.1 XHTML 264 4.8.2.2 Voice XML 266 4.8.2.3 WAP, XHTMLMP and WML 267 4.8.2.4 Synchronized Multimedia Integration Language (SMIL) 269 4.8.2.5 XML DTD, Schema and Other Features 271 4.9 IP MOBILITY 273 4.9.1 Mobile IP 274 4.9.2 Application-Layer Mobility 275 4.9.3 Cellular IP 276 4.10 OBJECT-BASED SOFTWARE TECHNOLOGIES 277 xiv The Multimedia Internet

4.10.1 JAVA and C# 279 4.10.2 CORBA and SOAP 281 4.10.3 Networked Services Environments 286 4.10.4 OpenCable Applications Platform 289

5. MEDIA PROTOCOLS AND APPLICATIONS 293 5.1 VOICE OVER IP (VoIP) 294 5.2 MULTIMEDIA CONFERENCING PROTOCOL H.323 300 5.3 MEGACO/H.248 305 5.4 SESSION INITIATION PROTOCOL (SIP) 309 5.4.1 Stream Control Transport Protocol (SCTM) 313 5.4.2 LDAP and H.350 Directory Services 314 5.5 RESERVATION PROTOCOL (RSVP) 315 5.6 REAL-TIME PROTOCOL (RTP) 318 5.7 MEDIA STREAMING AND THE REAL-TIME STREAMEVJG PROTOCOL (RTSP) 324 5.7.1 Media Streaming Modes 325 5.7.2 RTSP 327 5.7.2.1 Session Definition Protocol (SDP) 328 5.7.2.2 RTSP Operation 329 5.8 REAL-TIME STREAMING SYSTEMS 335 5.8.1 Video on Demand Streaming: Server Systems 335 5.8.2 Internet 342 5.9 COMMERCIAL STREAMING SYSTEMS 345 5.9.1 RealNetworks' Streaming System 346 5.9.2 Microsoft Windows Media 9^^ 352 5.9.3 The Apple QuickTime^M System 354 5.9.4 The Digital Fountain^"^ Media Streaming System 357 5.10 LOOKING TO THE FUTURE 360

References 361 Index 375