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Re: Why do so few mail providers support Port 587?

  • From: Paul Vixie
  • Date: Thu Feb 24 17:49:37 2005

> On Tue, Feb 15, 2005 at 09:00:11PM -0500, Sean Donelan wrote:
> > Although RFC2476 was published in December 1998, its amazing how few
> > mail providers support the Message Submission protocol for e-mail on
> > Port 587.  Even odder, some mail providers use other ports such as 26
> > or 2525, but not the RFC recommended Port 587 for remote authenticated
> > mail access for users.

well, in sbc-dsl-land, port 25 and port 587 are blocked, but port 26 gets
through.  it seems bizarre that port 587 would ever be blocked, but when
i encountered it, port 26 was my next choice.  perhaps other e-mail providers
had the same problem and used the same plan-b.

> > What can be done to encourage universities and other mail providers
> > with large roaming user populations to support RFC2476/Port 587?
> Give a good reason. That is still the missing part.

it's smtp that only works if you can authenticate.  thus it's only useful
for your own user population, and completely safe to leave open to the world
(as long as your user population keeps their passwords safe, that is.)
Paul Vixie