[caops-wg] Requirements and rationale for Relying Party Defined Namespace Constraints (signing_policy file)

[David Chadwick]

Mike Helm wrote:
> David Chadwick writes:
>> Hi Mike
>>
>> there is more to it than what you propose, and this is the second point 
>> I make ie. whether 2 different users can be given the same DN or not by 
>> different CAs (we assume that the same CA will be competent enough to 
>> not do that). If the answer is yes, then your whole infrastructure is 
>> broken. If the answer is no, then the sentence below should be changed 
> 
> Well, in the long long ago, the signing policy was in fact designed 
> for just this situation: CA A & CA B both certify subject name
> X.  Relying party has to decide which one of these versions of X
> it is willing to trust (or both or neither).
> 
> We don't allow this problem to exist in IGTF accredited CAs by
> policy. 

A very sensible policy.

regards

David


  And it is generally agreed that such collisions are so
> undesirable that this policy is not controversial.  There is
> nothing that can be done  about non-accredited CAs (such as government
> or commercial CAs for instance), altho many of them constrain
> their namespaces adequately so as not to be a problem.
> 

-- 

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David W. Chadwick, BSc PhD
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