This is a script I run on my local remote machine to open an ssh tunnel through my server at home, configured to allow ssh tunneling, so I can directly access ports on pcs behind the firewall, on my local machine!
When run, this will open port 8686 on my local computer. That is forwarded through a tunnel through my home server to a pc serving a webpage behind the firewall.
Then I would access http://localhost:8686 in a web browser, and I would be able to see that webpage running on port 80 on another server I have behind the firewall on my home network! Just replace ports and ip/domain names in my script for RDP ports and programs.
In short, yes it is. Any protocol can use this feature.
#!/bin/bash
# Tunnels to server behind firewall #localport#:#ipbehindfw#:#portbehindfw#
ssh -f khamil8686@nerd-exchange.com -L 8686:192.168.86.248:80 -N