The issues Ballew raises on network monitoring are very well considered, and just about everyone would do well to read this before pursuing this topic too far. There's also especially good coverage of the use of a version control system for managing changes to router configuration files, a hot button of mine. If you're not doing this, you should be, and this book tells you how. The final two chapters cover connecting to the outside world and network security. The chapter on exterior connections is decent, though not quite up to the quality of the rest of the book.
Exterior routing as a whole is still an unexplored area in the literature.
Ballew rightly points out that just the topic of BGP configuration issues could easily fill a book by itself. This is true, and it's a book that would be well received. The network security chapter does a good job defining the issues and a very good job of not trying to be the end-all authority on this. Instead, the basics are presented here, and the reader is then referred to other good sources for the details. Surprisingly few authors do this, and it's very refreshing.