Outgoing SMTP Servers

Jeroen van Aart jeroen at mompl.net
Wed Oct 26 00:28:13 UTC 2011

Owen DeLong wrote:
> It's both unacceptable in my opinion and common. There are even those
> misguided souls that will tell you it is best practice, though general agreement,
> even among them seems to be that only 25/tcp should be blocked and that
> 465 and 587 should not be blocked.

 From my consumer POV.

If you get a static IP with your provider, whether it is home internet 
or co-location, there should not be anything blocked. You're paying 
extra for the static IP in the case of home internet and the least you 
can expect is no blocking. Otherwise what's the point?

You can always block/cancel later in case of abuse obviously.

Of course this (and the below) does not apply in case of dynamically 
assigned IPs to a pool of home internet users.

> Best practice is to do what works and block as much SPAM as possible without
> destroying the internet in the process. There are those who argue that blocking
> 25/tcp does not destroy the internet. By and large, they are the same ones who
> believe NAT was good for us.

There shouldn't be any spam filtering or blocking on a static IP at the 
ISP level. The ISP should limit itself to filtering at their own mail 


Earthquake Magnitude: 3.6
Date: Tuesday, October 25, 2011 18:20:24 UTC
Location: Arizona
Latitude: 34.8137; Longitude: -112.5391
Depth: 5.00 km

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