Dr. Dobb's Journal July 2000
Although ATM may receive more attention in the technical and trade literature, frame relay dominates the market for wide-area data networks and will continue to do so for years to come. Frame relay was intended to be a high-speed replacement for X.25 packet switching technology by providing a streamlined packet format, control signaling on a separate logical connection, and a set of congestion-control tools. It has succeeded in driving off X.25 and, so far, has held off the challenge from ATM, which is even more streamlined and provides a more sophisticated congestion control and traffic-management facility. Four recent books provide excellent documentation of frame relay.
Of the four books I examine here, the clearest technical presentation is in Frame Relay: Technology and Practice, by Jeff Buckwalter. Following a brief overview and a discussion of the Standards bodies involved, Buckwalter provides an overall description of the frame relay architecture and looks at the various ways in which a frame relay interface connects to the network. Next, he presents a good chapter on frame relay virtual circuits; this includes a discussion of the differences between switched and permanent virtual circuits and a brief description of the frame relay signaling protocol. The most impressive part of Frame Relay: Technology and Practice comes next -- two chapters dealing with traffic management and the engineering of frame relay networks to implement traffic management. The book includes numerous illustrations that help to clearly explain the multiple approaches to congestion control and traffic management defined in the frame relay Standards. The remainder of the book (about half) deals with issues of interest to a network manager. There is a discussion of the network-management tools available within the Standard. Then, the book looks at issues related to frame relay service pricing and procurement, including a discussion of the RFP process. Buckwalter presents several case studies to illustrate how to exploit frame relay features to meet specific requirements. The book concludes with a discussion of voice over frame relay and internetworking with frame relay. The book also includes a useful 40-page glossary. In summary, Frame Relay: Technology and Practice is comprehensive and clear. Although it does not cover all of the technical aspects of frame relay in detail, it is the best book if you want a broad, yet technical, treatment of the subject.
In Frame Relay Networks, Uyless Black covers the same material as the first half of Buckwalter, with more detail in some areas, especially signaling. Black does a fine job of explaining protocols and technology. If your focus is solely the frame relay Standards and you have an interest in the technical details, this book may be the best choice.
Also, like Buckwalter's book, Walter Goralski's Frame Relay for High-Speed Networks aims to provide a technical treatment of frame relay combined with a look at network-management issues. The bulk of the book is devoted to a discussion of frame relay Standards. While the treatment is worthwhile and detailed, Goralski uses few illustrations, which makes for somewhat dryer reading. The latter part of the book deals with network management, voice over frame relay, and frame relay internetworking. If you are looking for a more detailed technical treatment than Buckwalter and a broader treatment than Black, Frame Relay for High-Speed Networks is a good choice.
Frame Relay Internetworking, by Liza Henderson and Tom Jenkins, is aimed at a less technical audience, such as business and IT managers. The first 60 pages provide a technical overview of frame relay protocols and traffic management. The next few chapters deal with user issues, including why and when to use frame relay, connection options, and a discussion of types of frame relay service providers and the services they offer. The book then talks about frame relay support for SNA and voice. One chapter is devoted to how to protect a frame relay network from failures. Frame Relay Internetworking next treats network-management issues, including relating application requirements to frame relay services, connecting frame relay with ATM, operations and management issues, and managing service-level agreements. Finally, the book offers advice for designing a corporate network that includes frame relay and developing an RFP. Overall, it does an excellent job of covering the issues that a manager would find of interest.
DDJ