1. Chapter 1 Introduction to SSH

   1. What Is SSH?

   2. What SSH Is Not

   3. The SSH Protocol

   4. Overview of SSH Features

   5. History of SSH

   6. Related Technologies

   7. Summary

2. Chapter 2 Basic Client Use

   1. A Running Example

   2. Remote Terminal Sessions with ssh

   3. Adding Complexity to the Example

   4. Authentication by Cryptographic Key

   5. The SSH Agent

   6. Connecting Without a Password or Passphrase

   7. Miscellaneous Clients

   8. Summary

3. Chapter 3 Inside SSH

   1. Overview of Features

   2. A Cryptography Primer

   3. The Architecture of an SSH System

   4. Inside SSH-1

   5. Inside SSH-2

   6. As-User Access (userfile)

   7. Randomness

   8. SSH and File Transfers (scp and sftp)

   9. Algorithms Used by SSH

   10. Threats SSH Can Counter

   11. Threats SSH Doesn't Prevent

   12. Summary

4. Chapter 4 Installation and Compile-Time Configuration

   1. SSH1 and SSH2

   2. F-Secure SSH Server

   3. OpenSSH

   4. Software Inventory

   5. Replacing R-Commands with SSH

   6. Summary

5. Chapter 5 Serverwide Configuration

   1. The Name of the Server

   2. Running the Server

   3. Server Configuration: An Overview

   4. Getting Ready: Initial Setup

   5. Letting People in: Authentication and Access Control

   6. User Logins and Accounts

   7. Subsystems

   8. History, Logging, and Debugging

   9. Compatibility Between SSH-1 and SSH-2 Servers

   10. Summary

6. Chapter 6 Key Management and Agents

   1. What Is an Identity?

   2. Creating an Identity

   3. SSH Agents

   4. Multiple Identities

   5. Summary

7. Chapter 7 Advanced Client Use

   1. How to Configure Clients

   2. Precedence

   3. Introduction to Verbose Mode

   4. Client Configuration in Depth

   5. Secure Copy with scp

   6. Summary

8. Chapter 8 Per-Account Server Configuration

   1. Limits of This Technique

   2. Public Key-Based Configuration

   3. Trusted-Host Access Control

   4. The User rc File

   5. Summary

9. Chapter 9 Port Forwarding and X Forwarding

   1. What Is Forwarding?

   2. Port Forwarding

   3. X Forwarding

   4. Forwarding Security: TCP-wrappers and libwrap

   5. Summary

10. Chapter 10 A Recommended Setup

    1. The Basics

    2. Compile-Time Configuration

    3. Serverwide Configuration

    4. Per-Account Configuration

    5. Key Management

    6. Client Configuration

    7. Remote Home Directories (NFS, AFS)

    8. Summary

11. Chapter 11 Case Studies

    1. Unattended SSH: Batch or cron Jobs

    2. FTP Forwarding

    3. Pine, IMAP, and SSH

    4. Kerberos and SSH

    5. Connecting Through a GatewayHost

12. Chapter 12 Troubleshooting and FAQ

    1. Debug Messages: Your First Line of Defense

    2. Problems and Solutions

    3. Other SSH Resources

    4. Reporting Bugs

13. Chapter 13 Overview of Other Implementations

    1. Common Features

    2. Covered Products

    3. Table of Products

    4. Other SSH-Related Products

14. Chapter 14 SSH1 Port by Sergey Okhapkin (Windows)

    1. Obtaining and Installing Clients

    2. Client Use

    3. Obtaining and Installing the Server

    4. Troubleshooting

    5. Summary

15. Chapter 15 SecureCRT (Windows)

    1. Obtaining and Installing

    2. Basic Client Use

    3. Key Management

    4. Advanced Client Use

    5. Forwarding

    6. Troubleshooting

    7. Summary

16. Chapter 16 F-Secure SSH Client (Windows, Macintosh)

    1. Obtaining and Installing

    2. Basic Client Use

    3. Key Management

    4. Advanced Client Use

    5. Forwarding

    6. Troubleshooting

    7. Summary

17. Chapter 17 NiftyTelnet SSH (Macintosh)

    1. Obtaining and Installing

    2. Basic Client Use

    3. Troubleshooting

    4. Summary

1. Appendix A SSH2 Manpage for sshregex

2. Appendix B SSH Quick Reference

   1. Legend

   2. sshd Options

   3. sshd Keywords

   4. ssh and scp Keywords

   5. ssh Options

   6. scp Options

   7. ssh-keygen Options

   8. ssh-agent Options

   9. ssh-add Options

   10. Identity and Authorization Files

   11. Environment Variables

3. Colophon

Our look is the result of reader comments, our own experimentation, and feedback from distribution channels. Distinctive covers complement our distinctive approach to technical topics, breathing personality and life into potentially dry subjects. The animal on the cover of SSH, the Secure Shell: The Definitive Guide is a land snail (Mollusca gastropoda).

A member of the mollusk family, a snail has a soft, moist body that is protected by a hard shell, into which it can retreat when in danger or when in arid or bright conditions. Snails prefer wet weather and, though not nocturnal, will stay out of bright sun. At the front of a snail's long body are two sets of tentacles: its eyes are at the end of one set, and the other set is used for smelling and navigation.

Land snails are hermaphrodites, each having both female and male sex organs, though a snail must mate with another snail in order for fertilization to occur. A snail lays eggs approximately six times a year, with almost 100 eggs each time. Young snails hatch in a month and become adults in two years. A snail's life span is approximately 5-10 years.

Known as a slow mover, a snail moves by muscles on its underside that contract and expand, propelling the snail along at a slow pace. It leaves a wet trail of mucus, which protects the snail from anything sharp it may need to crawl over as it searches for food. The snail's diet of plants, bark, and fruits causes it to be a pest in many parts of the world where it is notorious for destroying crops. Mary Anne Weeks Mayo was the production editor and copyeditor for SSH, the Secure Shell: The Definitive Guide. Colleen Gorman proofread the book. Rachel Wheeler and Jane Ellin provided quality control. Matt Hutchinson and Lucy Muellner provided production assistance. John Bickelhaupt revised the index.

Ellie Volckhausen designed the cover of this book, based on a series design by Edie Freedman. The cover image is an original engraving from the book Natural History of Animals by Sanborn Tenney and Abby A. Tenney, published by Scribner, Armstrong & Co. in 1873. Emma Colby produced the cover layout with QuarkXPress 4.1 using Adobe's ITC Garamond font.

David Futato and Melanie Wang designed the interior layout based on a series design by Nancy Priest. Mike Sierra implemented the design in FrameMaker 5.5.6. The text and heading fonts are ITC Garamond Light and Garamond Book; the code font is Constant Willison. The illustrations that appear in the book were produced by Robert Romano using Macromedia FreeHand 8 and Adobe Photoshop 5. This colophon was written by Nicole Arigo.