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Re: automated processing of generalized certificates



At 20:32 2/29/96, Neal McBurnett wrote:

[lots of good stuff -- valuable suggestions, IMO]

One nit:

>Another high-level sort of semantics we need to capture is the
>rules for "chaining" of certificates.  E.g. PGP allows chaining of
>email identity certs.  I've done a study of the 'web of trust'
>that is generated by that, available at
>        http://bcn.boulder.co.us/~neal/pgpstat/
>
>Rules like which types of certificates (Meaning-Registered major
>type?) can chain to which other certificates, perhaps how long a chain
>can be, the need for multiple independent paths, etc. might be
>specified or left to user specification.

PGP's web of trust, if it means anything at all, is like a sociogram.
It tells who has met whom, for key signing.  Some of those meetings
aren't physical, even....  That kind of linkage might dilute with
distance.

The linkage in a certificate chain is different.  The Issuer needs
the authority to be an Issuer of that particular Meaning cert -- and
ditto, his Issuer.  This chain of meanings would usually differ at
each link in the chain and there's no reason it would be size limited.
There's a clear need for setting out, in a cert's Meaning, what
rights and attributes this cert assigns to the signed key -- and
therefore what that signed key can do for a living...or, as you said,
"which types of certificates [...] can chain to which other certificates".


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