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Re: Rethink CRLs

At 08:45 AM 8/15/96 +1000, Michael Warner wrote:

>Surely the only meaning that a CRL has is to negate any meaning the original
>certificate had (after a certain time).
>In revoking a certificate, the CA is effectively saying "I am no longer willing
>to guarantee the binding between this public key and this identity (or whatever
>else the certificate is binding to the public key)".
>While the reason for this revocation may be of interest to curious humans, it's
>effect on applications should be the same regardless of the reason - don't use
>the certificate because it is not valid.
>Anything else and you are moving toward "analogue certificates", which express
>a degree of confidence that an identity is bound to a key.   Now that really
>will add to complexity !


        there's a difference between "this private key is no longer good as
of <date>", "this private key was in the hands of the enemy between <date1>
and <date2> but it's back now", and "this private key went bad sometime, but
we don't know when, so don't trust it even from the beginning".

        Especially when it's a CA's private key, the result of those three
different interpretations is quite different.

 - Carl

|Carl M. Ellison          cme@cybercash.com   http://www.clark.net/pub/cme |
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