Linux Routing Author: Joe "Zonker" Brockmeier, Dee-Ann LeBlanc, & Ronald W. McCarty, Jr. Pages: 328 Publisher: New Riders ISBN: 1-57870-267-4 Summary: Some good, some not so good, but probably worth it if you'll be routing with Linux. Review Date: 23 May, 2003

I'll begin this review with a disclaimer. I'm a database/systems type, so routing, packets, and networking, while interesting, aren't necessarily topics that send tingles of enthusiasm down my spine. So there may be biases in my review that surface accordingly . . . You've been warned.

Linux Routing is an introduction to routing concepts in general as well as other networking topics, all with a focus on implementing the technologies covered on Linux systems. The target audience of the book is "experienced Linux users and administrators." Newbies might find some information of value, but will likely find a lot of knowledge that is simply assumed of the reader.

So what does it cover? To begin with, if you're looking for coverage of firewalls, ipchains, iptables and friends, you're probably not looking for this book. The book does discuss these topics, but only very superficially. New Riders does have another book titled Linux Firewalls which may provide better coverage on those topics. The principal focus of Linux Routing is using Linux machines as routers. The first half of this book covers that topic fairly well, but once into the later chapters, it meanders superficially through several related topics.

To begin with, the first few chapters cover the various routing protocols available for your use, and the underlying algorithms that power these protocols. Compared to other sources I've read, the coverage of algorithms here was confusing at times, and the diagrams did little to help. The target audience, with some effort, could probably follow along, as did I, but in my estimation, the algorithms could have been explained more clearly. As a database guy, this talk of protocols was just a bit dry for my taste. YMMV. Coverage here includes RIP-1, RIP-2, OSPF, MOSPF, DVMRP, and PIM, with discussions of applications of these protocols, where appropriate, in both unicast, and multicast environments. The book then moves on to discuss border routing protocols, including IGP, EGP, BGP, BGMP, and MSDP. Finishing out this section is a very good chapter on IPV4 and IPV6 addressing.

The book continues with coverage of the various Linux daemons available to manage these protocols, with very detailed coverage of configuration options available with each daemon. In some cases it's almost too regurgitated though. There are quite a few examples provided, but they are usually very short clips demonstrating a particular configuration option. It would be nice if the authors had provided a few complete configuration examples, just to give a big-picture feel to the discussion. Following this is good coverage of PPP and rip2ad.

To this point, the book does a fairly good job at its task, and by this point you should probably have enough information to get you on your way to building a router out of a Linux box. The rest of the book is where the meandering starts. There is some good information to be had, but much of what's offered is superficial in nature. It's almost as if the authors at this point had said all they were going to say about the meaty topics, and just needed filler for the rest of the book. As an example, there is a chapter covering the basic network commands, friends like ping, traceroute, ifconfig, etc. For the target audience of experienced Linux users and administrators, this is helpful review, but not all that informational.

Other topics covered in this half of the book include planning router layout and function, linux routing basics (but wasn't that what the first chapters were all about?), discussion of the various hardware you might find yourself using, building a kernel suitable for a router, security and NAT, and monitoring and analysis tools. It's a lot of topics, but again, mostly superficial coverage. There is some value in these chapters, though, by way of helpful recommendations, and pitfalls you may want to avoid, good practical tips here and there that will probably be valuable in your router project.

So after my less than enthusiastic comments, will you want to buy this book? If you plan on turning a Linux box into a router, then yes, you'll probably find a lot of valuable information and pratical wisdom here, but be prepared to wade through a fair amount of fluff towards the end.

As a final note, as of the time of this review, the book is starting to show its age a little, what with the kernel being the rapidly moving target that it is, but most of what's covered will still be applicable in general.

Overall rating: 7/10