Amazon.com just posted my four star review of Richard Deal's Cisco Router Firewall Security. I read half of it on the flight from DC to San Francisco, and the rest on the return leg. From the review:
"I really enjoyed reading Cisco Router Firewall Security (CRFS) by Richard Deal. This book delivers just what a technical Cisco book should: discussion of concepts, explanation of command syntax, and practical examples. The author offers several ways to solve a security problem and then recommends his preferred choice. He correctly leans towards applying cryptography when available and avoids clear-text authentication methods or control channels. If you avoid the first chapter and keep a few minor caveats in mind, I would consider CRFS to be a five-star book."
If you administer Cisco routers, I highly recommend reading this book.