Re: [dmarc-ietf] Doing a tree walk rather than PSL lookup

Alessandro Vesely <vesely@tana.it> Tue, 24 November 2020 12:20 UTC

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From: Alessandro Vesely <vesely@tana.it>
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Subject: Re: [dmarc-ietf] Doing a tree walk rather than PSL lookup
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On Mon 23/Nov/2020 22:38:46 +0100 John Levine wrote:
> In article <9f388e33-c15d-9fcc-e9d3-d7719288fb98@gmail.com> you write:
>>On 11/23/2020 1:04 PM, Jesse Thompson wrote:
>>> I meant to suggest that the requirement for a tree walk would be that the Organizational Domain would need to have that in its policy. 
>> It seems like a decent compromise for the people worried about unnecessary DNS lookup overhead.
> 
> If I'm going to go to the effort to download and decode a PSL and find the OD, I'll just use the OD.
> 
> One of the points of the tree walk is to get rid of the PSL processing.


The PSL processing is a local lookup on an in-memory suffix tree.  How is it a 
progress to replace it with a tree walk?  A PSL search is lightning faster than 
even a single DNS lookup, isn't it?


Best
Ale
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