Re: [spfbis] Local macros strike again, was Suggestion...

[Philip Gladstone <[e-mail]>]

On 1/18/2012 5:46 AM, Hector Santos wrote:
> I have a hard time understanding why would any system screw around
> with a guessing game  of "SPF default record" with completely not
> possibility for actual accuracy and yet, expect there would not be
> problem or rather begin to use this as some basis that something is
> broken about SPF!  I don't get it Doug. This would is already random.
> I see no way to presume there is a default SPF record without falling
> into trouble.
>
> Now, if it was fundamentally the case that Senders *always* used an
> machine among the Receiveer network of MX host IP addresses, then I
> can see some default rules.  Sure.  But that is not reality. There is
> no requirement that a Sender machine must be part of any RECEIVER (MX)
> network.  This applies closer to smaller systems but not with larger
> network systems and not even with smaller systems.
>
> I just don't see why you think this has any value.
>
I think that the question could be rephrased as:

For a particular receiving MTA, for all mail senders who do not publish 
an SPF record, does the addition of "a mx/24 ~all" improve spam 
detection accuracy or not?

It is clear that using this record will cause all spam to be marked as 
~. Depending on your spam detection algorithm, this may be the level 
that you would select if there was no SPF processing. If this is the 
case, then the "a mx/24" record will only improve the situation.

Philip

-- 
Philip Gladstone
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