- From: tommy lindberg <lindberg_tommy@hotmail.com>
- Date: Thu, 20 May 2004 09:30:41 +0000
- To: stephen.farrell@cs.tcd.ie
- Cc: www-xkms@w3.org
Thanks for that Stephen - that clears things up. Plus I don't have to correct my samples for that reason ;) Regards Tommy >From: Stephen Farrell <stephen.farrell@cs.tcd.ie> >To: tommy lindberg <lindberg_tommy@hotmail.com> >CC: www-xkms@w3.org >Subject: Re: minutes online ... 11 may, 2004 telecon >Date: Wed, 19 May 2004 17:04:49 +0100 > > > >Tommy, > >>>>If the responder is not required to return both values when present in >>>>the underlying PKI then he is potentially giving the relying party an >>>>incorrect view of the validity interval. > >But that may well be intended and correct. (Nit picking: the >"validity interval" at the end of that sentence refers to the >underlying PKI and not the the XKMS client/responder model which >may involve something entirely different. So maybe you should >more properly talk about "a" validity interval, and not "the" >validity interval"?) > >>>>E.g. consider the case where both attributes are left out by the >>>>responder although they exist in the underlying PKI; according to >>>>paragraph [193] the relying party will think that the binding is valid >>>>at any time which is not what the PKI thinks. > >No. The absence of the information implies whatever the xkms >responder's stated policy says it means, and nothing else! > >For example, a valid (and useful IMO) model for use of XKMS which >shows why you may want to sometimes ingore the underlying PKI is >where a CA is revoked, (and no replacements issued), in >particular due to cessation of biz. Now that invalidates a lot >of X.509 paths, but I can imagine lots of cases where it remains >correct for an xkms responder to continue to serve the keys of >that (revoked) CA's subjects as "good" - say for an application >that wants to (re-) check an old signature (and perhaps where >the responder "knows" those keys remain ok since they're >"local"). > >Another less radical model would be where an xkms responder might >include NotOnOrAfter information which reflects the CRL issuance >frequency, so the binding (and *not* the key!) is good only for >say an hour/minute/second into the future. > >Lastly, an xkms responder might choose to never respond with a >binding that appears to make a claim about the history of a key, >as opposed to its current state - so NotBefore is always "now". >For many applications, there's probably no harm at all in such >amnesia! > >Convinced? >Stephen. > _________________________________________________________________ Help STOP SPAM with the new MSN 8 and get 2 months FREE* http://join.msn.com/?page=features/junkmail
Received on Thursday, 20 May 2004 05:31:17 UTC