The Internet Protocol Journal - Volume 2, No. 1

Book Review

Book Review

IP Multicasting

IP Multicasting: The Complete Guide to Interactive Corporate Net-works, by Dave Kosiur, ISBN 0-471-24359-0 Wiley Computer Publishing, 1998, There is nothing remarkable about the statement: As technology becomes more affordable, applications once limited to power users find their way to the mainstream desktop. Video streaming, audio streaming, collaborative applications, and videoconferencing are all examples of applications once found exclusively on high-end workstations but now making their way to the mainstream desktop. If widespread deployment of these applications is to occur, we must be prepared to supply a supporting infrastructure.

The use of IP multicasting is gaining popularity, but many of the fundamentals that drive this and other network technologies, such as routing protocols and transport protocols, are still being debated. This book supplies a comprehensive view of the state-of-the-art as well as practical procedures one can follow in order to incorporate mulitcasting into existing network topologies.


Chapter 2 presents an introduction to TCP/IP basics and routing. Chapter 3, The Basics of Multicasting, addresses three sender-based multicasting protocols (ST-II, XTP, and MTP) and concentrates on IP multicast (a receiver-based multicasting protocol). The book would be much easier to follow if this chapter had been combined with Chapter 6.

Chapter 4, Multicast Routing Concepts, Chapter 5, Multicast Routing Protocols, and Chapter 6, Transport Protocols, constitute the heart of this book.

Beginning with basic concepts of unicast routing and routing algorithms, the author extends the models to deal with the problems of routing multicast data. Tree maintenance techniques form the bulk of Chapter 4.

Chapter 5 covers four multicast routing protocols: Distance Vector Multicast Routing Protocol (DVMRP); Multicast Open Shortest Path First (MOSPF); Protocol Independent Multicast (PIM); and Core-Based Trees (CBT). Placing the emphasis on PIM, Kosiur covers both PIM-SM (sparse mode) and PIM-DM (dense mode). He does a nice job of describing each of the protocols and summarizes each by reviewing its advantages and disadvantages. Finally, the author concludes by examining ways of achieving interdomain routing and protocol interoperability.

In Chapter 6, Kosiur provides an overview of the Real-Time Transport Protocol (RTP)/Real-Time Transport Control Protocol (RTCP) and the Real-Time Streaming Protocol (RTSP).

In addition, he discusses a dozen or more multicast protocols, all trying to answer the question: "How is retransmission of lost packets handled?" He classifies the protocol approaches into receiver-based or sender-based. In my opinion, this is the most interesting problem of multicasting. Answer this question wrong, and you find yourself with a nonscalable network cluttered with acknowledgments (ACKs).

Chapters 4 through 7 all consider delivering Quality of Service and so I was a little surprised to see Chapter 7 devoted to the subject.

Kosiur provides a good introduction to RSVP (Resource ReserVation Protocol), but until we see RSVP in wide deployment I would look at the previous three chapters for practical knowledge on the topic. In Chapter 7, and then in Chapter 11 he covers a lot of practical issues concerning Quality of Service, as well as ways to support multicasting over various networks, such as ATM, Frame Relay, and ISDN/dialup networks.

Chapter 9 is a compilation of some free and commercial software packages that use multicasting. Chapter 10 covers Mbone (the Multicast backbone), a popular experimental multicasting network. It is arguable that the state of multicasting wouldn't be where it is today without the Mbone.

A C+

This book rates a C+. Kosiur certainly has an understanding of the material, but his descriptions are neither clear nor concise. Reading this book is difficult, and learning from it even more so, but better organization could turn it into a gem.

-Neophytos Iacovou University of Minnesota Academic & Distributed Computing Services