Re: [Asrg] [ASRG] SMTP pull anyone?

Alessandro Vesely <> Tue, 18 August 2009 12:51 UTC

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Date: Tue, 18 Aug 2009 16:52:27 +0400
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Subject: Re: [Asrg] [ASRG] SMTP pull anyone?
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Steve Atkins wrote:
> On Aug 17, 2009, at 8:38 PM, John Levine wrote:
>>> The model is like a simple C/R involving Message ID of a mail. The 
>>> sending domain provides the Message ID and allows computational time 
>>> for the receiving domain and then query the sending domain to send 
>>> the message.
>> This model has been proposed many, many, times before.  I suppose we should
>> make a page for it in the ASRG wiki of anti-spam techniques even though it's
>> more of a mail system redesign than an anti-spam measure.

Agreed; however, I'm out of office this week, and will consider 
doing this only when I'll be back. (As a new entry in 
I suppose).

IMHO, this model --this instance of it-- stems from the common 
qui pro quo generated by speaking of clients (or servers) as if 
they were hosts, rather than processes: Most spam comes from 
clients, I want to eliminate it, hence I will only pull mail 
from servers.

> If you do, mention RFC 2017.

Good point. External-Body resembles "SMTP pull", except for 
implying that the content should be retrieved by the MUA.

RFC 2111's mid URLs could be used to retrieve a message sent by 
SMTP (or stored via IMAP) if access by Message-ID were provided.

In order to infringe the Tumbleweed patent, AFAICS, one 
additionally has to automate checking the log file, as an 
alternative to positive DSNs for the externally stored content.