Border Gateway Protocol (BGP) does exactly what its name implies--it routes traffic efficiently from its origin on one network to its destination on another. Most typically, it's the protocol that provides a private network with Internet connectivity. Internet Routing Architectures is an authoritative text on BGP in theory and practice, covering everything from good design of BGP-based internetworks to actual implementation of those internetworks on Cisco Systems routers. This second edition includes more information than its predecessor on BGP-4; other improvements are updates rather than major additions or revisions. You will appreciate having this book on hand if your job has to do with optimizing traffic under BGP, or if you're preparing for one of the Cisco certification exams.

Sam Halabi--a respected authority on Cisco routers--discusses addressing schemes and the ways in which routing protocols operate within those schemes. The general information serves mainly to set the stage for BGP, which Halabi explains lucidly in theory before getting into design issues and, finally, implementation via router configuration. The book presents practical situations ("Multihoming to a Single Provider," for example, which is subsequently broken down into sub-scenarios about how the multiple connections are used) and steps through the design decisions associated with them. It's also big on diagrams and uses one on nearly every other page to drive home points. The result: this book earns its cover price as a tutorial and as a reference. --David Wall

Topics covered: Means of connecting one network to another, especially by means of Border Gateway Protocol 4 (BGP-4) on Cisco Systems routers. There's coverage of addressing and routing-protocol generalities, as well as of BGP tuning for routing inside and outside autonomous systems. Design decisions are a big part of this book's scope.