Outgoing SMTP Servers

Keith Medcalf kmedcalf at dessus.com
Mon Oct 31 22:19:59 CDT 2011

Dave CROCKER [mailto:dhc2 at dcrocker.net] said on Sunday, 30 October, 2011 22:41

> On 10/30/2011 8:36 PM, Brian Johnson wrote:
>> So you support filtering end-user outbound SMTP sessions as this is a
>> means to prevent misuse of the Commons*. Correct?

> If it is acceptable to have the receiving SMTP server at one end of a
> connection do filtering -- and it is -- then why wouldn't it be acceptable to have
> filtering done at the source end of that SMTP connection?
> As soon as we step upstream this way, stepping up earlier still is merely
> a question of efficacy and efficiency.

Actually, if it is my network I have the absolute right to control what comes in and what goes out.  If I am a commercial entity and my paying customers like this, then I will make lots of money.  If they don't, I will go out of business.  Thus for self-interest and survival end-user-networks do not restrict outbound excessively but block inbound with various policies that strike a balance between paying customers going elsewhere and paying customers leaving for less controlled environments, while still making a profit and staying in business.

Hence, we end up with the situation that we have.  It won't change without either (a) every operator deciding to do the same thing for their own collective best interest (such as blocking outbound TCP/25); or, (b) external fascist forces.

And the bit-movers really don't care, since all they do is move bits...and more bits means more money.

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