> > > Interestingly, when I telnet from _outside_ the network to my > > firewall's port 2320, it works, but Telnet goes into line mode rather > > than character mode! > > Probably, as I think someone said, telnet noticing it's not using the > standard telnet port and not even trying to go character-at-a-time. > > I did a telnet myself, snooping the network traffic, and... > > me -> you SYN > you -> me SYN|ACK > me -> you ACK > you -> me data: IAC WILL ECHO > me -> you data: IAC DO ECHO > you -> me data: \r\n DECTEN, PANDA TOPS-20... > > Nowhere, in particular, is there any attempt at LINEMODE negotiation. > And, when I type ?, nothing is sent until I press RETURN, upon which my > end sends ?\r\n. >
I tried doing a similar test to Mouse for comparison given that my telnet client seems to be producing the desired behaviour (whether by accident or by design I am not sure). Here are the results and my interpretation of them which may not be correct as I am a bit rusty on this stuff: me -> you SYN you -> me SYN|ACK me -> you ACK you -> me data: fffb 0100 0000 (IAC WILL ECHO) me -> you data: fffd 03ff fd01 (IAC DO SUPPRESS GO AHEAD, IAC DO ECHO) you -> me data: fffb 0300 0000 (IAC WILL SUPPRESS GO AHEAD) me -> you ACK you -> me data: \r\n DECTEN, PANDA TOPS-20... Regards, Peter Coghlan.
