Why do so few mail providers support Port 587?

Fri Feb 25 15:47:59 UTC 2005

On Thu, Feb 24, 2005 at 04:02:20PM -0700, Smoot Carl-Mitchell wrote:

> On Thu, 2005-02-24 at 17:14 -0500, Jim Popovitch wrote:
> > If supporting one port is y hours of time and headache, then two ports
> > is closer to y*2 than y (some might argue y-squared).  587 has some
> > validity for providers of roaming services, but who else?  Why not
> > implement 587 behavior (auth from the outside coming in, and accept all
> > where destin == this system) on 25 and leave the rest alone?
> I did run into a case where supporting port 587 was useful. I found out
> the hard way that one Internet service provider for hotels blocked
> outbound port 25, but not 587. So sending outbound mail to my mail relay
> would have been impossible without support for port 587.

It's so funny. On this list many argued Port 25 outgoing must
be blocked only to notice, that users actually seem to need it to
send mail. Now we must configure our mailservers to listen on 587 to
circumvent these filters, that were stupid in the first place.

Now to my prophecy mode: Spammers will start using 587 to spam, which we
then also all block outgoing, notice again that customers still want to
send mail and open another port ... 652 maybe. But this in a
"while (true)" loop until we run out of ports.

This is completely ridiculous.

Nils