[pkix] Proposal for working on PKIX revocation open issues

["Dr. Massimiliano Pala" <[e-mail]>]

Dear PKIX Enthusiasts,

Although great work has been done in the past... 20 years.. (?) on 
providing very good protocols in the PKIX work, I think that we all 
agree that we still have some unresolved issues. In particular, the 
revocation is still a hot topic (especially for online environments) 
could use improvement over the current status of things. In particular, 
by looking at current specifications, some work is needed to address 
concerns especially in non-web environments.

For example, current specifications about OCSP stapling do not address 
the case of client authentication (which is a widespread use case 
outside the web environment) or, again, defining some new transport 
protocols for delivering OCSP responses which might reduce operational 
costs for revocation service providers.

After proposing the idea to Stephen Farrell and Kathleen Moriarty, we 
would like to know if there might be interests in participating in 
updating the status of the current revocation mechanisms for PKIX. This 
said, the scope of the work I am proposing is very limited. Specifically:

(a) Defining new transport protocols for revocation information 
availability (e.g., OCSP over DNS or OCSP over LDAP)
(b) (Possibly) defining a more lightweight revocation mechanisms (e.g. 
Lightweight Revocation Tokens)
(c) (Possibly) helping other working groups to revise and update how 
revocation information are provided (e.g., the client authentication case)
(d) (Possibly) introducing privacy consideration when it comes to 
revocation checking

Because of these considerations, I am proposing to start a conversation 
- for now, Stephen and Kathleen suggested we use (or "abuse") the "The 
Right Key" mailing list to see if there might be enough interest in the 
work from implementers to address these issues. I know that we (OpenCA) 
are interested in implementing these features, and we would like that 
the work would be standardized.

At minimal, I would like (a) to happen. This could be achieved in 6 
months (and we might not even need to meet). (b) and (c) are also 
desirable in order to provide better support for non-browsers and small 
devices (AFAIK, some work might be relevant for DICE). (d) is something 
that we should, I think, all be mindful and at least some considerations 
should be provided. The scope of the work, however, will be limited to 
revocation.

Please, if you are interested and would like to start the discussion, 
post your opinion on [e-mail] - also, please, circulate this 
proposal to anybody who might be interested in collaborating on this issue.

Please also note that we did decide not to use the [e-mail] mailing 
list because we thought [e-mail] might provide a more active 
pool of implementors.

Looking forward to receive all your inputs and start working on the topics.

Cheers,
Max