[118539] in North American Network Operators' Group
Re: ISP port blocking practice
daemon@ATHENA.MIT.EDU (Owen DeLong)
Thu Oct 22 23:58:44 2009
From: Owen DeLong <owen@delong.com>
In-Reply-To: <4761eff1fe5f8c51a625d6a3396bd4f8@yyc.orthanc.ca>
Date: Thu, 22 Oct 2009 20:51:09 -0700
To: "Lyndon Nerenberg (VE6BBM/VE7TFX)" <lyndon@orthanc.ca>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Oct 22, 2009, at 4:14 PM, Lyndon Nerenberg (VE6BBM/VE7TFX) wrote:
>> Few
>> companies use the MSP port (tcp/587).
>
> Can you elaborate. Is this based on analysis you've conducted on
> your own network? And if so, is the data (anonymized) available for
> the rest of us to look at?
>
> My experience is that port 587 isn't used because ISPs block it
> out-of-hand. Or in the case of Rogers in (at least) Vancouver, hijack
> it with a proxy that filters out the AUTH parts of the EHLO response,
> making the whole point of using the submission service ... pointless.
>
> --lyndon
>
Wow... That's evil. Most ISPs I've dealt with don't have that
problem, but,
if I encountered one that did, I'd vote with my feet in short order.
Owen
