Introduction to SSH Secure Shell
SSH Secure Shell is a program that allows secure network
services over an insecure network, such as the Internet.
The Secure Shell concept originated on UNIX as a replacement
for the insecure "Berkeley services", that is, the
rsh
, rcp,
and rlogin commands.
SSH Secure Shell replaces other, insecure terminal applications
(such as Telnet and FTP).
It allows you to securely login to remote host computers,
to execute commands safely in a remote computer,
to securely copy remote files,
to forward X11 sessions (on UNIX),
and to provide secure encrypted and authenticated
communications between two non-trusted hosts. Also arbitrary
TCP/IP ports can be forwarded over the secure channel, enabling
secure connection, for example, to an email service.
SSH Secure Shell with its array of unmatched security features
is an essential tool in today's network environment. It is a
powerful guardian against the numerous security hazards that
nowadays threaten network communications.
This chapter gives an overview of some of the security risks
facing the Internet user and introduces the SSH2 protocol to
combat these risks.
