Subject: [ietf-dkim] List of Verifiers Methods

From: Hector Santos <[email-masked]>
Date: Sat, 28 Aug 2010 01:44:52 -0400

Is there a list, and if not, can we together gather a list of verifier 
methods in practice?   It think it will help provide "a reason" for 
greater understanding how DKIM can be useful and maybe help better 
market DKIM and  existing methods, and/or even create synergism for 
creating more uniform methods.

Off hand I see two classifications, where the top level is:

   o AUTHOR-PRACTICE
   o SENDER-PRACTICE
   o RECEIVER-PRACTICE

and under each one you have a secondary classification describing 
specific verifier or validation methods.

Some of these classification would be common to all. For example

   DKIM-ADSP

falls under AUTHOR-PRACTICE but also technically falls under 
SENDER-PRACTICE and RECEIVER-PRACTICE as well.  I can see a table or 
outline such as the following

   o AUTHOR-PRACTICE
       - DKIM-ADSP
   o SENDER-PRACTICE
       - DKIM-ADSP
   o RECEIVER-PRACTICE
       - DKIM-ADSP

I think it would be helpful if we can collect verifier DKIM signature 
validation methods in practice or even new ideas for verifiers.

Based on what gather over the course of many years participating in 
the WG, I see as verifier methods available and/or discussed:

   DKIM-ADSP      Author Domain Signing Practice - IETF WG proposal
   DKIM-TPA       3rd party Authorization - Doug Otis's IETF I-D
   DKIM-SSA       Special Signing Arrangements (YAHOO)
   DKIM-STATS     Bayesian, Neural Net, AI or similar (SpamAssassin)
   DKIM-SPF       DKIM plus SPF "combo" logic?
   DKIM-REP       Reputation services (?)

And any other people know of. I guess that includes also:

   DKIM-VBR       Levine's Vouch-By-Reference

but that might fall under DKIM-REP.  Maybe DKIM-REP is too general and 
this level of classification needs to show specific verifier methods, 
but I have no problem if these include available vendor proprietary 
DKIM-REP services.

Anyway, I am just suggesting this and others with more exposure to 
this can perhaps lock these down better than I could. I think it will 
help more developers to implement DKIM with more verifier ideas.  I 
see many MTA that added DKIM-CORE signing only but no substance on the 
DKIM verifier said.

-- 
Hector Santos, CTO
http://www.santronics.com
http://santronics.blogspot.com

_______________________________________________
NOTE WELL: This list operates according to 
http://mipassoc.org/dkim/ietf-list-rules.html