SSH: The Secure Shell
The Definitive Guide

by Daniel J. Barrett, Ph. D., Richard E. Silverman, and Robert G. Byrnes.

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This site is operated by the authors of the O’Reilly book on SSH. The first edition was published in February of 2001, by Dan Barrett and Richard Silverman. Joined by Robert Byrnes, we completed the second edition in May of 2005.

We have also written O’Reilly’s Linux Security Cookbook.

Here are a few articles by the authors:

• Richard Silverman
• dsniff and SSH:
  Reports of My Demise Are Greatly Exaggerated
• Time and Tide Wait For No Protocol:
  The SSH Keystroke Timing Attack of Song, Wagner, and Tian
• Top Ten Secure Shell FAQ’s
• Robert Byrnes
• Secure Cooking with Linux, Part 1
• Secure Cooking with Linux, Part 2
• Secure Cooking with Linux, Part 3
• Saving Our Bacon: Snort Security Holes and Strategies for Safe Network Monitoring

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What is SSH?

SSH is a tool for secure remote login over insecure networks. It provides an encrypted terminal session with strong authentication of both the server and client, using public-key cryptography. Features include:

• a variety of user authentication methods
• tunneling arbitrary TCP connections through the SSH session, protecting normally insecure protocols such as IMAP and allowing secure passage through firewalls
• automatic forwarding of X windows connections
• support for external authentication methods, including Kerberos and SecurID
• secure file transfers

SSH is based on IETF standard protocols.