This book will provide system administrators with all of the information as well as software they need to run Ethereal Protocol Analyzer on their networks. There are currently no other books published on Ethereal, so this book will begin with chapters covering the installation and configuration of Ethereal. From there the book will quickly move into more advanced topics such as optimizing Ethereal's performance and analyzing data output by Ethereal. Ethereal is an extremely powerful and complex product, capable of analyzing over 350 different network protocols. As such, this book will also provide readers with an overview of the most common network protocols used, as well as analysis of Ethereal reports on the various protocols. The last part of the book will provide readers with advanced information on using reports generated by Ethereal to both fix security holes and optimize network performance.