If you've managed Linux/Unix machines recently you are probably familiar with SSH, or secure shell. It replaces popular commands such as telnet, rsh, rlogin, and ftp with secure and encrypted applications that do the same thing. If you login to remote machines or transfer confidential data over the Internet you cannot afford not to know about SSH.

This book by Daniel J. Barrett, Richard E. Silverman and Robert G. Byrnes, is, as it is titled, the definitive guide to SSH. It not only covers the various clients and servers available for SSH (and operating systems), it covers many different applications and uses of SSH. From connection tunneling to SOCKS proxies to automated batch jobs, any administrator will find novel and new uses for SSH in this book.

Having received this book to review from O'Reilly, I read it cover to cover. I do not suggest you do this (if you value your sanity). It is by no means designed to be that kind of book. However, this book is invaluable as a reference to SSH where few other books exist. The organization is straight-forward and lends itself to reviewing specific functions without having to mine the entire volume to get the knowledge you seek.

If you administer systems you can't afford not to know about SSH, and this book is the best one around to learn it.

From Ravings of John C. A. Bambenek