ietf-smtp
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Re: port number for smtp over ssl

2003-01-16 09:25:24

ned+ietf-smtp,

Wednesday, January 15, 2003, 4:56:57 PM, you wrote:
In any case, the situation is what it is, and I do not think the
continued registration of POPS and IMAPS should not be taken as a
rationale for also registering SMTPS.

Hmmm. I focused so much on the existence of the practise that I probably
did not pursue a second point adequately:

   The views expressed on this list are directly in conflict with the
   views expressed among the ops community about blocking outbound port
   25 through firewalls.

This kills travellers. (And, no, simply using the "local" SMTP server is
not viable, primarily for reasons of trust, but also some concern for
reliability, given how differential ISP mail service is.)

I again repeat that this is exactly the problem that SMTP submission on
port 587 is intended to solve. You're not supposed to be able to use
port 587 for submission without authenticating first. This means it should
be safe to allow access to it for travellers.

I note in passing that the same cannot be said for SMTPS; allowing access to it
is effectively the same as allowing access to port 25 insofar as authentication
is concerned. So if the practice of using SMTPS truly became commonplace the
ops community would end up treating it in the same way as port 25.

At a minimum, there needs to be some dialogue between the ops community
and the email community to resolve this.

How should we proceed?

The email community has already specified a solution to this problem. All you
have to do is use it. I'm really not sure what else needs to be said.

                                Ned