Re: [Asrg] SMTP pull anyone?

Douglas Otis <> Mon, 17 August 2009 17:15 UTC

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From: Douglas Otis <>
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Subject: Re: [Asrg] SMTP pull anyone?
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On 8/17/09 9:34 AM, Michael Thomas wrote:
> I don't see how push or pull fundamentally changes the spam
> equation in any case. The problem wrt spam is the any-any nature
> of who you receive communication from, not who initiates the
> connection.

The pull concept is fairly simple.  When creating a white-list, it 
becomes important to identify the source of the message.  Since email 
uses store and forwarding, originating sources of messages can be 
difficult to determine, based upon the message alone.  Of course DKIM 
helps with that, but it would be more ideal to shift a greater portion 
of the burden toward the sender for email to continue to scale.

By exchanging only references to messages that are held on-line, the 
message itself does not need to be initially exchanged.  When contacted 
by a specific source that has been white-listed, your MUA could fetch 
the desired message from the on-line server at the same time references 
have been retrieved.

When a reference has been falsified, no message can be fetched.  This 
would not demand cryptographic efforts by the sender, or expect receipt 
of an exponentially increasing volume of junk, or tens or hundreds of 
DNS transactions per domain to resolve server authorizations.

One wonders whether IMAP might be tweaked to provide an online function 
rather than using traditional URIs.  The problem should not be viewed as 
the 80-20 rule where 80% of the problems are caused by 20% of the 
sources.  This should be viewed as the 99-99 rule, in today's email