SSH Tunnels: Bypass (Almost) Any Firewall

The goal of this article is to present a few effective methods to
revamp the way you work in a restricted corporation-like network. In
order to achieve it we.re going to use SSH tunneling to bypass the
firewall rules applied by your system administrator. We.ll start with
breaking through simple restrictions and gradually pass to more and
more elaborate firewalls while we move on. This article is a
continuation of a previous text: SSH tricks published in our vortal
last month. The spirit of this article is a little bit different,
though. It targets more experienced users, especially those who have
to work in computer networks with harsh security rules. To make it
clear - using SSH to tunnel insecure protocols like FTP or CVS is not
in the scope. Perhaps another SSH article will cover this.

http://www.linuxsecurity.com/content/view/124671