Jonathan Feldman has done a good job at putting together a reasonably entertaining and fairly easy read here. The problem with it is that there are far too many errors, and the information that IS correct is not explained very well. My learning and experience as a CCNA gave me a solid understanding of most of this material, fortunately. I bought this book for a quick review of the major exam objectives, which it provided well enough. My previous knowledge, however, made apparent the very large gaps, lack of explanation or background, and relatively poor concept treatment contained in this book. Bottom line: If you have a firm knowledge of networking already, this book may be a humorous and quick review of the salient points. However, if you already are that prepared, there's nothing you will gain from this book anyway. For the less experienced, I'm afraid the information contained in Mr. Feldman's guide will ony serve to confuse. There are better guides available.