Port forwarding means
encapsulating any TCP-based communication between the client and
the server programs within an SSH session. This feature allows any
TCP-based application or service to take advantage of all the benefits
of SSH. SSH allows you to establish a "secure tunnel" between
two hosts. After you have set up a secure tunnel, the participating
applications operate transparently. For example, when you forward
a regular TELNET connection
through SSH, all information, including your user name, password,
and actual data, are automatically encrypted and checked for integrity.
SSH port forwarding includes additional features for encrypting
the X protocol (for X Window Systems). Using SSH, you can invoke
X programs on a remote machine and have them appear on your local
display. In this case, all X-protocol data is secured. For more
information, see
Port Forwarding.
HP TCP/IP Services for OpenVMS Guide to SSH
Secure Shell Overview
