According to the Release Manual for that router, it's not built in out of the box.
Does this mean for definite that it doesn't support it? Not necessarily. They may release updates for it. Looking at some of the commands they ask you to type in with
telnet, it seems like it may be running Linux. Can you do an
ls or a
pwd to get paths or files? Maybe the router supports Tomato or DD-WRT, and those two would give you SSH access.
To get SSH access though, your router needs to support it, which is usually just an additional service. If you are concerned about having a secure connection from the outside world into it, I'd recommend having a small Linux box (for example, on a Raspberry Pi) running the SSHd daemon, then telnet from that to the router. If you are looking for an encrypted connection from your workstation inside the network to the router, I'd look at figuring out why there are peering eyes on your network.
I realize this may not answer the question, but hopefully it gives you some info, and other ideas of where to look or what to do.