As of December 2001, I don't know of any other books which ostensibly cover the topic of policy routing for Linux. Since I think this book does provide some real value about the topic, I guess that makes it the best book available right now, and so I think this is pretty much a "must have" book for anyone who wants to get all the information they can.
Some things I expected to get from this book were: clear detailed explanations of the "ip", "tc", and "iptables" commands, some explanations of the "netlink"/"rtnetlink" interfaces, clear explanations of the concepts and data structures those things are addressing, explanations of the various queueing disciplines available and when are the best times to use each them, explanations of how to troubleshoot and debug problems caused by all these things; and lots of clear and thorough diagrams, since to me that is a critical part of explaining any networking/routing topic.
In my opinion the book pretty much provided none of those things. However, it did present some buzzwords in appropriate contexts, and provided some information about the kinds of things which can be done with respect to policy routing with Linux and what is generally meant by "policy routing", and it provided some useful opinions and insight into various issues.
I think the book provides some value as perhaps an "introduction to policy routing concepts and Linux for network administrators". Also, I guess in a perfect world it would go without saying that the author is clueful about the topic of the book, but nowadays that does not seem to be a prerequisite to writing a book like this. I think this author _is_ clueful about this topic.
