Introduction

Cisco Systems, Inc., is the leading global supplier of internetworking hardware and software, with more than 100,000 devices deployed throughout public and private internetworks each year. At the time of this writing, these devices carry more than 80 percent of the public Internet's traffic. The aim of this book is to help novice Cisco users with the basic administration of their internetworking devices.

Each of these devices has Cisco proprietary operating system software called the Cisco Internetwork Operating System (IOS). The Cisco IOS software is a complicated real-time operating system consisting of multiple subsystems and tens of thousands of possible configuration parameters. Using straightforward, chronological descriptions and practical examples, this book focuses on the Cisco IOS software with respect to configuring, operating, and maintaining internetworking devices. In addition to covering general aspects of the IOS, we consider it in the context of the three most popular networking protocols used today: the Transmission Control Protocol/Internet Protocol (TCP/IP), Novell Inc.'s Internetwork Packet Exchange (IPX), and Apple Computer Inc.'s AppleTalk.