h a CCNA or equivalent (or greater) knowledge should benefit from this book. My goal in writing Network Warrior is to explain complex ideas in an easy-to-understand manner. While the book contains introductions to many topics, you can also consider it as a reference for executing common tasks related to those topics. I am a teacher at heart, and this book allows me to teach more people than I'd ever thought possible. I hope you will find the discussions I have included both informative and enjoyable. I have noticed over the years that people in the computer, networking, and telecom industries are often misinformed about the basics of these disciplines. I believe that in many cases, this is the result of poor teaching, or the use of reference material that does not convey complex concepts well. With this book, I hope to show people how easy some of these concepts are. Of course, as I like to say, "It's easy when you know how," SO I have tried very hard to help anyone who picks up my book understand the ideas contained herein. If you are reading this, my guess is that you would like to know more about network- ing. So would I! Learning should be a never-ending adventure, and I am honored that you have let me be a part of your journey. I have been studying and learning about computers, networking, and telecom for the last 24 years, and my journey will never end. This book attempts to teach you what you need to know in the real world. When should you choose a layer-3 switch over a layer-2 switch? How do you tell if your network is performing as it should? How do you fix a broadcast storm? How do you know you're having one? How do you know you have a spanning-tree loop, and how do you fix it? What is a T1, or a DS3 for that matter? How do they work? In this book, you'll find the answers to all of these questions, and many, many more. Net- work Warrior includes configuration examples from real-world events and designs, and is littered with anecdotes from my time in the field-I hope you enjoy them. Conventions Used in T