:
:
>> ...
>> > Telnet options, and for that matter speed, happen after the 3-way
>> > handshake. We're not getting that far.
>> >
>> > --Steven M. Bellovin, Steven M. Bellovin
>>
>> Steve, I defer to your expertise, as always. ;-]
>
>
>Nevertheless ... I went looking for comments on how this was being done,
>and found the following specualtion by a small number of different
>people.
>
>"SEF [is] unique in that it can detect what appear to be telnet
>connections to Port 25 and drop the connection. This is probably because
>telnet connections send one character at a time whereas real SMTP
>clients send all the strings at once."
>
>This would not require the 3WH, ISTM.Sure it would -- until the 3-way handshake, there's no application data
flowing, and hence no characters being sent one at a time.
Right. Doh. Me go home lie down rest.
We'll leave to another mailing list the question of what security
benefit there is to such a feature...
