I have both "Enable Telnet" and "Enable SSH" turned on. However, when I try to connect to my RT-AC66U with putty using SSH (port 22) it says "Network error. Connection refused" (or something like that). If I switch connection method from SSH to Telnet (port 23) it becomes possible to connect. I wonder if ssh protocol is supported at all. If it is, then what application is used as the SSH server? I haven't noticed any sshd in the router firmware.