Cisco designed the Internetwork Operating System (IOS) to adapt to many different situations, which is part of the reason it has so many commands — the official documentation fills more than a foot of shelf space! Cisco Field Manual: Router Configuration extracts the most widely used router commands from that body of documentation and, without dumbing them down at all, presents them in a way that's extremely helpful to people who want straightforward answers about what they need to do in order to make their equipment do what they want. The best way to use this book — and it's a great value for everyone short of a very experienced IOS expert — is to look in the index for the subject that interests you (configuring access lists around NetBIOS names, for example, or setting up Quality of Service for voice traffic), then flip to the pages that explain what you need to do.

For the purpose of exploring a typical example of this book's coverage, suppose you want to provide Dynamic Host Configuration Protocol (DHCP) services with your Cisco router. This book, in a three-page spread that combines explicit command listings with explanatory text and background information, tells you exactly what to do at the IOS command line. Where you have a choice to make, such as whether you want to specify a Domain Name Service (DNS) server in your DHCP broadcast, it's clear what your options are and how to implement all possible choices. After the step-by-step procedure that covers all typical cases, there's a complete example — in the form of a complete input and output listing from the IOS command line — that shows the configuration process from start to finish.