13 Dec
2016
13 Dec
'16
8:56 a.m.
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.