Hi Alexey,

>>>> Some mailers offer telnet as a method of transferring messages/files,
>>>> kind of like binkp does.
>>> ITN means "ifcico with Telnet-style connection control"
>> Yes, BBBS provides a telnet mailer interface which operates as Nick
>> and you mention. It is a mailer interface, not for users,

> Does it really use Telnet-style connection control?
> If yes, I'd like to see the full session recording (with `tcpdump`).

Yes, it uses telnet connections via mailer:

===
    75.117.66.119.23 > 72.43.242.234.52263: Flags [P.], cksum 0xf087
    (correct), seq 795:797, ack 441, win 33600, options [nop,nop,TS val 40927
    ecr 283519449], length 2
            0x0000:  4500 0036 814b 0000 2c06 4475 4b75 4277  E..6.K..,.DuKuBw
            0x0010:  482b f2ea 0017 cc27 64f2 602d 8629 f872 H+.....'d.`-.).r
            0x0020:  8018 8340 f087 0000 0101 080a 0000 9fdf  ...@............
            0x0030:  10e6 29d9 4f4f                           ..).OO
                15:47:06.448764 IP (tos 0x0, ttl 50, id 30474, offset 0, flags
[DF], proto
TCP (6), length 40)
===

I hope this clip is enough to see it.. I saved the whole connection session
though if you want to see it all - there were a number of other connections via
binkp with other nodes at the time.  This is a pw protected session with
1:3634/12's telnet node.   I don't usually use this tool so at the moment the
results mean nothing to me 

Take care,
Janis

--- BBBS/Li6 v4.10 Dada-1