IP MULTICAST WITH APPLICATIONS TO IPTV AND MOBILE DVB-H

IP MULTICAST WITH APPLICATIONS TO IPTV AND MOBILE DVB-H Daniel Minoli A JOHN WILEY & SONS, INC., PUBLICATION

IP MULTICAST WITH APPLICATIONS TO IPTV AND MOBILE DVB-H

IP MULTICAST WITH APPLICATIONS TO IPTV AND MOBILE DVB-H Daniel Minoli A JOHN WILEY & SONS, INC., PUBLICATION

Copyright Ó 2008 by John Wiley & Sons, Inc. All rights reserved Published by John Wiley & Sons, Inc. Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 750-4470, or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley.com/go/permission. Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. For general information on our other products and services or for technical support, please contact our Customer Care Department within the United States at (800) 762-2974, outside the United States at (317) 572-3993 or fax (317) 572-4002. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic formats. For more information about Wiley products, visit our web site at www.wiley.com. Library of Congress Cataloging-in-Publication Data Minoli, Daniel, 1952- IP multicast with applications to IPTV and mobile DVB-H / Daniel Minoli. p. cm. Includes bibliographical references and index. ISBN 978-0-470-25815-6 (cloth) 1. Webcasting. 2. Internet television. 3. Digital video. I. Title. TK5105.887M578 2008 006.7 dc22 2007038116 Printed in the United States of America 10987654321

For Anna and the kids. And for my parents Gino and Angela Also thanking Mike Neen

CONTENTS Preface About the Author xiii xv 1 INTRODUCTION TO IP MULTICAST 1 1.1 Introduction 1 1.2 Why Multicast Protocols are Wanted/Needed 3 1.3 Basic Multicast Protocols and Concepts 5 1.4 IPTV and DVB-H Applications 11 1.5 Course of Investigation 21 Appendix 1.A: Multicast IETF Request for Comments 21 Appendix 1.B: Multicast Bibliography 23 References 23 2 MULTICAST ADDRESSING FOR PAYLOAD 26 2.1 IP Multicast Addresses 26 2.1.1 Limited Scope Addresses 29 2.1.2 GLOP Addressing 30 2.1.3 Generic IPv4 Addressing 30 2.2 Layer 2 Multicast Addresses 31 2.2.1 Ethernet MAC Address Mapping 31 2.3 MPEG-Layer Addresses 33 References 38 3 MULTICAST PAYLOAD FORWARDING 39 3.1 Multicasting on a LAN Segment 40 3.2 Multicasting between Network Segments 40 3.3 Multicast Distribution Trees 41 3.4 Multicast Forwarding: Reverse Path Forwarding 47 3.5 Multicast Forwarding: Center-Based Tree Algorithm 48 3.6 Implementing IP Multicast in a Network 49 References 50 vii

viii CONTENTS 4 DYNAMIC HOST REGISTRATION INTERNET GROUP MANAGEMENT PROTOCOL 51 4.1 IGMP Messages 52 4.2 IGMPv3 Messages 55 4.3 IGMP Operation 61 Appendix 4.A: Protocol Details for IGMPv2 63 4.A.1 Overview 63 4.A.2 Protocol Description 64 4.A.3 Receiver (Host) State Diagram 65 4.A.4 Router State Diagram 69 Appendix 4.B: IGMP Snooping Switches 72 Appendix 4.C: Example of Router Configurations 76 References 77 5 MULTICAST ROUTING SPARSE-MODE PROTOCOLS: PROTOCOL INDEPENDENT MULTICAST 78 5.1 Introduction to PIM 79 5.2 PIM SM Details 83 5.2.1 Approach 86 5.2.2 PIM SM Protocol Overview 86 5.2.3 Detailed Protocol Description 94 5.2.4 Packet Formats 114 References 124 6 MULTICAST ROUTING SPARSE-MODE PROTOCOLS: CORE-BASED TREES 125 6.1 Motivation 126 6.2 Basic Operation 127 6.3 CBT Components and Functions 129 6.3.1 CBT Control Message Retransmission Strategy 131 6.3.2 Nonmember Sending 131 6.4 Core Router Discovery 131 6.5 Protocol Specification Details 132 6.5.1 CBT HELLO Protocol 133 6.5.2 JOIN_REQUEST Processing 134 6.5.3 JOIN_ACK Processing 135 6.5.4 QUIT_NOTIFICATION Processing 135 6.5.5 ECHO_REQUEST Processing 136 6.5.6 ECHO_REPLY Processing 137

CONTENTS ix 6.5.7 FLUSH_TREE Processing 137 6.5.8 Nonmember Sending 138 6.5.9 Timers and Default Values 138 6.5.10 CBT Packet Formats and Message Types 138 6.5.11 Core Router Discovery 142 6.6 CBT Version 3 145 6.6.1 The First Step: Joining the Tree 145 6.6.2 Transient State 146 6.6.3 Getting On Tree 146 6.6.4 Pruning and Prune State 147 6.6.5 The Forwarding Cache 147 6.6.6 Packet Forwarding 148 6.6.7 The Keepalive Protocol 148 6.6.8 Control Message Precedence and Forwarding Criteria 149 6.6.9 Broadcast LANs 149 6.6.10 The all-cbt-routers Group 150 6.6.11 Nonmember Sending 150 References 151 7 MULTICAST ROUTING DENSE-MODE PROTOCOLS: PIM DM 152 7.1 Overview 152 7.2 Basic PIM DM Behavior 153 7.3 Protocol Specification 155 7.3.1 PIM Protocol State 156 7.3.2 Data Packet Forwarding Rules 158 7.3.3 Hello Messages 159 7.3.4 PIM DM Prune, Join, and Graft Messages 160 7.3.5 State Refresh 170 7.3.6 PIM Assert Messages 175 7.3.7 PIM Packet Formats 182 References 184 8 OTHER DENSE-MODE MULTICAST ROUTING PROTOCOLS: DVMRP AND MOSPF 185 8.1 Distance Vector Multicast Algorithm 185 8.1.1 Overview 185 8.1.2 Basic DVMRP Operation 186

x CONTENTS 8.2 Multicast OSPF 190 References 193 9 IP MULTICASTING IN IPv6 ENVIRONMENTS 194 9.1 Opportunities Offered by IPv6 194 9.2 Introductory Overview of IPv6 196 9.2.1 IPv6 Benefits 197 9.2.2 Traditional Addressing Classes for IPv4 198 9.2.3 Network Address Translation Issues in IPv4 199 9.2.4 IPv6 Address Space 200 9.2.5 Basic Protocol Constructs 201 9.2.6 IPv6 Autoconfiguration 204 9.3 Migration and Coexistence 208 9.4 Multicast with IPv6 211 9.4.1 IPv6 Multicast Addresses 211 9.4.2 MAC Layer Addresses 211 9.4.3 Signaling 213 9.4.4 RP Approaches 213 References 213 10 MULTICAST LISTENER DISCOVERY 215 10.1 Overview of MLDv1 216 10.2 Message Format 216 10.3 Protocol Description 218 10.4 Node State Transition Diagram 220 10.5 Router State Transition Diagram 223 10.6 Overview of MLDv2 226 10.6.1 Protocol Overview 227 10.6.2 Building Multicast Listening State on Multicast Address Listeners 228 10.6.3 Exchanging Messages between the Querier and the Listening Nodes 228 10.6.4 Building Multicast Address Listener State on Multicast Routers 230 10.7 Source Filtering 232 References 233

CONTENTS xi 11 IPTV APPLICATIONS 234 11.1 Overview and Motivation 234 11.2 Basic Architecture 236 11.2.1 Content Aggregation Subsystem 244 11.2.2 Uniform Transcoding Subsystem 245 11.2.3 Conditional-Access Management Subsystem 251 11.2.4 Encapsulation Subsystem 258 11.2.5 Long-Haul Distribution Subsystem 262 11.2.6 Local Distribution Subsystem 264 11.2.7 Middleware Subsystem 267 11.2.8 Set-Top Boxes 267 11.2.9 Catcher (for VoD Services) 269 Appendix 11.A: Serial Digital Interface Basics 269 Appendix 11.B: MPEG Basics 271 11.B.1 MPEG-2 Transport/Multiplexing Mechanisms 271 11.B.2 IPTV/IP Transmission over TS Logical Channels 279 11.B.3 Compression Technology 281 Appendix 11.C: Encapsulation for Transmission of IP Datagrams over MPEG-2/DVB Networks 298 References 300 12 DVB-H: HIGH-QUALITY TV TO CELL PHONES 303 12.1 Background and Motivation 304 12.2 Basic DVB-H Technology 311 12.2.1 DVB-H Mobile Devices 315 Appendix 12.A: Open Mobile Video Coalition Efforts 317 References 318 Glossary 319 Index 349

PREFACE This book updates early-release published work undertaken by the author in the early-to-mid-1990s on the topic of video-for-telcos ( telco TV ), video-over-packet, video-over-dls, and video-over-atm contained in the book Video Dialtone Technology: Digital Video over ADSL, HFC, FTTC, and ATM, McGraw-Hill, 1995, and based on extensive hands-on work on broadband communications and digital video/digital imaging. At this juncture, the focus of this book (and for this industry) is completely on commercial-quality video over IP, IPTV. Of late there has been renewed interest in IP multicast protocols and technologies because of the desire by traditional telephone companies to deliver entertainment-level video services over their network using next-generation infrastructures based on IP networking, by the cell phone companies for video streams to hand held telephone sets and personal digital assistants (PDAs), and by the traditional TV broadcast companies seeking to enter the same mobile video market. Critical factors in multicasting include bandwidth efficiency and delivery tree topology optimization. IP multicast technology is stable and relatively easy to implement, particularly for architecturally simple (yet large) networks. A lot of the basic IP multicast mechanisms were developed in the mid-to-late 1980s, with other basic work undertaken in the 1980s. A number of recent functional enhancements have been added. From a commercial deployment perspective, IP multicast is now where IP was in the mid-1990s: poised to take off and experience widespread deployment. Examples of applications requiring one-to-many or many-to-many communications include but are not limited to digital entertainment video and audio distribution, multisite corporate videoconferencing, broad distribution financial data, stock quotes and news bulletins, database replication, software distribution, and content caching (for example, Web site caching). The text literature on IP multicast is limited and somewhat dated, particularly in reference to IPTV applications. This compact text is intended for practitioners that seek a quick practical review of the topic with emphasis on the major and most-often used aspects of the technology. Given its focus on IPTV and DVB-H it can also be used by technology integrators and service providers that wish to enter this field. Following an introductory discussion in Chapter 1, Chapter 2 covers multicast addressing for payload distribution. Chapter 3 focuses on multicast payload forwarding. Chapter 4 covers the important topic of dynamic host registration using the Internet Group Management Protocol. Chapter 5 looks at multicast routing in sparse-mode environments and the broadly used PIM-SM. Chapter 6 discusses CBT. Chapter 7 looks at multicast routing for dense-mode protocols and PIM-DM in particular. Chapter 8 xiii