[ietf-dkim] draft-ietf-dkim-mailinglists-02 review

[Michael Thomas]

On 09/13/2010 11:58 AM, Murray S. Kucherawy wrote:
>> -----Original Message-----
>> From: ietf-dkim-bounces at mipassoc.org [mailto:ietf-dkim-bounces at mipassoc.org] On Behalf Of Michael Thomas
>> Sent: Monday, September 13, 2010 10:22 AM
>> To: Ian Eiloart
>> Cc: DKIM
>> Subject: Re: [ietf-dkim] draft-ietf-dkim-mailinglists-02 review
>>
>> I really don't know why people who should know better are clinging onto
>> this
>> nostalgic notion that SMTP-time isn't the right (only) place to do
>> scanning,
>
> Given that I'm currently a strong believer in domain reputation being a big part of the future, I've asked that question internally here, and I'm told in return that people believe the cost incurred by switching to end-of-DATA filtering vs. connect-time filtering is a lot larger than I believe.  And they [claim to] have the data to support that position from large customers, so for now I'm not arguing it.

I assume you're talking about IP address based reputation which can be done once the incoming connect is completed.
I've heard the same thing, but I'm always a little bit dubious about "can't be done" kinds proclamations. They
almost always forget to take into account Moore's Law and clever workarounds. Luckily, IP address base filtering
isn't a zero sum game with DKIM so the argument is largely academic.

>
>> but there is a layer violation issue with MLM's. Unless you have a MLM
>> that
>> is completely purpose-built with SMTP, or has bits and pieces of itself
>> inserted into
>> milter-like parts of the SMTP stream, your average MTA is going to have
>> no clue whether it's destined for a MLM or anything else.
>
> Those points might well encourage future MLMs to be implemented with much tighter MTA integration, but if so, we can be sure there will always be the legacy stuff hanging around as drag.

Yes, that's exactly what I was thinking -- there's a lot of legacy out there that either on auto-pilot, or has
no reason to change. Even though I don't think we should be let the MLM-tail wag the email dog, saying that we
think that layering violations are a Good Thing leaves a bad taste in my mouth.

Mike