SSH tunneling is a way to transfer any kind of Internet data through a secure SSH connection. A single SSH connection can carry more than one SSH tunnels, each of these tunnels serving a single TCP port (i.e. typically a service like mail, WWW or MySQL).

An typical usage example is a tunnel to read your mail over the secured IMAP protocol: the tunnel starts at your computer at port 143 (IMAP) and is carried by SSH to your mail server at port 143 (IMAP). Once the tunnel is established, instead of connecting to servername.joyent.us:143, you connect to localhost:143; all data is then funneled through the secure tunnel.

• To use a SSH tunnel, follow the instructions in the Tunneling section of the SSH Guide.