Why do so few mail providers support Port 587?

Fri Feb 25 11:08:57 UTC 2005

Nils Ketelsen wrote:

>On Tue, Feb 15, 2005 at 09:00:11PM -0500, Sean Donelan wrote:
>
>  
>
<snip>

>>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.
>  
>
For the above population good reasons include being able to properly 
support such users. An alternate port is already a neccessity with many 
current providers.

And your benefit? You get to standardize your support for your users 
stranded behind a port 25 block. You get to treat all 587 connections as 
requiring authentication to succeed, and by mere fact of their 
existence, are authenticated. You get to add another line item/RFC to 
the list of services your enhanced commercial services support.

You dont want to formalize support? OK then add this to your 
sendmail.mc, make a note on your change forms and have it done with.

DAEMON_OPTIONS(`Port=submission, Name=MSA, M=Ea')dnl
DAEMON_OPTIONS(`Port=smtps, Name=MTAS, M=Eas')dnl
^
+-------------For sendmail 8.13+

And our benefit? We get an environment where 587 authenticated sending 
is the norm. We can turn on SPF. We can require users to use their "home 
isp" mail servers. We get MUA which default setup includes probing for 
TLS/SMTP AUTH 587 submission during setup.

We all win.

MTA implementors? If 587 is the norm, yet it allows un-authenticated 
direct-to-mx spam bombarding by default, it *will* be included in 
outbound port-25 blocks. And then it will lose its relevance.

We all lose.

>
>Nils
>
>
>  
>