Marc Haber wrote:
> On Tue, 15 Jan 2008 14:01:20 -0800, Jeroen van Aart
> <kroshka@???> wrote:
>> What is wisdom in this mess? Insist on everyone using port 587? ignore
>> 587 and support a host of legacy clients with port 465 and allow port 25
>> for submissions? Open all 3 ports and allow whatever people want on any
>> port? Users have been told for years to use 25 (and 465), to add to the
>> confusion.
>>
>> Out of curiosity, why is it so wrong to use 465? It's just a port
>> number, not a religion. :-) Instead of choosing another port, those who
>> "decide" (who?) could have renamed port 465 to read "submission". Or not?
>
> Please do not confuse two things: On tcp/587, you are expected to
> speak cleartext ESMTP first and can _optionally_ use STARTTLS to
> convet an already built connection to encryption ("SMTP over TLS over
> SMTP").
>
Yes - with the qualifiers, 'Expected' or 'by convention' or 'for
broadest compatibility with current MUA' or even 'to possible problesm
of your own making'.
But other security schemes are permitted on port 587, as they affect
only the 'local' implementation and that user community - not the
internet at large or users of OTHER servers or services.
> On tcp/465, it is expected to establish an encrypted connection first
> and then speak ESMTP ("SMTP over TLS").
It *was* so expected. Long ago.
Port 465 is reserved for IP Multicast, SSM and Cisco IP/TV
It has nothing to do with e-mail in general or smtp in particular.
Not for a long time now.
See:
http://www.iana.org/assignments/port-numbers
.. where it is as "igmpv3lite" on udp, and "urd" on tcp.
If you care what those actually mean, see also:
ftp://ftpeng.cisco.com/ipmulticast/config-notes/iptv34ssm.txt
>
> Two completely different and mutually incompatible things.
>
> Greetings
> Marc
>
Very different. Very incompatible.
smtp is complex enough without trying to carry it over multicast
internet television.
;-)
Bill
