Secure your computer network with SSH! With transparent, strong encryption, reliable public-key authentication, and a highly configurable client/server architecture, SSH (Secure Shell) is a popular, robust, TCP/IP-based solution to many network security and privacy concerns. It supports secure remote logins, secure file transfer between computers, and a unique ''tunneling'' capability that adds encryption to otherwise insecure network applications. Best of all, SSH is free, with feature-filled commercial versions available as well. SSH, The Secure Shell: The Definitive Guide covers SSH1, SSH2, and OpenSSH for Unix, plus Windows and Macintosh products. It shows you how to configure SSH servers and clients, both system-wide and per user; explains advanced key management using agents; and covers installing and maintaining SSH systems (with special tips for large data centers), forwarding (tunneling) of TCP and X11 applications, undocumented behaviors of popular SSH implementations, and how to troubleshoot a wide variety of common and not-so-common problems.