[ietf-dkim] draft-fenton-dkim-threats-00

[Jim Fenton]

Douglas Otis wrote:

>
> On Oct 5, 2005, at 9:57 AM, Hallam-Baker, Phillip wrote:
>
>> I read the threat analysis and agree with the content
>>
>> I think that we can elaborate the threats against DKIM  indefinitely. 
>> The important thing is that the threat analysis in  its current form 
>> answers the two major questions relevant at this  point:
>>
>> * What threat does DKIM defend against
>>
>> * Given the previous attempts to do this type of work why is DKIM  
>> likely to be more successful?
>
>
> I agree, there should be greater clarity with regard to realistic  
> defenses offered by the DKIM mechanism, especially in the third-party  
> scenario you described.

Do you really agree?  I read Phill's comment as "we could go on forever, 
but this is pretty good now" while I read yours as "needs improvement".

>
> ...
>
>> What DKIM does is to allow a party to accept responsibility for an  
>> email message. This is very different to the traditional S/MIME,  
>> PGP, PEM, MOSS objectives.
>
> ...
>
> Repudiation offers _minimal_ value when combined with an easy to  
> exploit mailbox-domain authorization scheme.  Abusers will adopt  
> requisite conventions that defeat repudiation.  Ascribing repudiation  
> as a goal would be a mistake when reputation _must_ be applied as a  
> defense.  However, with minor modification permitting replay  
> abatement, reputation should offer protection.

On good advice, I steered clear of the topic of repudiation.  Is there 
someplace the document implies repudiation protection?

-Jim