Re: SMTP Server Port Number

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Until the "transition" is complete, what does the RFC say is the proper SMTP
port???

Per the RFC:

Port 587 is reserved for email message submission as specified in
this document. Messages received on this port are defined to be
submissions. The protocol used is ESMTP [SMTP-MTA, ESMTP], with
additional restrictions as specified here.

While most email clients and servers can be configured to use port
587 instead of 25, there are cases where this is not possible or
convenient. A site MAY choose to use port 25 for message submission,
by designating some hosts to be MSAs and others to be MTAs.

So, per the definition from the RFC, Port 587 is for ESMTP, not SMTP.

Really, is all this hair-splitting necessary?


--?
Milly Staples [MVP - Outlook]

Post all replies to the group to keep the discussion intact. All
unsolicited mail sent to my personal account will be deleted without
reading.

After furious head scratching, N. Miller asked:

| On Fri, 12 Aug 2005 22:43:34 -0700, Milly Staples [MVP - Outlook]
| wrote:
|
|| I know there are alternate ports but by definition, SMTP uses Port
|| 25 by default.
|
| SMTP, by definition, is "Simple Message Transfer Protocol":
|
| http://www.faqs.org/rfcs/rfc2821.html
|
| Sending email from a client is no longer considered "message
| transfer"; and has not been since, oh, 1998. Sending email from a
| client has been defined as "message submission" since, oh, 1998:
|
| http://www.faqs.org/rfcs/rfc2476.html
|
| That last RFC defines the "message submission" port. Internet email is
| currently in a state of transition to the those not-so-new
| definitions.


.

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