About that "Mighty Fortress"... What's it look like?

[Ray Dillinger]

Assume, contra facto, that in some future iteration of PKI, it 
works, and works very well.  

What the heck does it look like?

At a guess....  Anybody can create a key (or key pair).  They 
get one clearly marked "private", which they're supposed to keep, 
and one clearly marked "public", which they can give out to anybody
they want to correspond with. 

Gaurantors and certifying authorities can "endorse" the public key
for specific purposes relating to their particular application.
Your landlord can "endorse" your keycard to allow you to get into 
the apartment you rent, the state government can "endorse" your 
key when you get a contractor's license or private investigator's 
license or register a business to sell to consumers and pay taxes,
etc.  

There are no certifying agencies other than interested parties 
and people who issue licenses/guarantees for specific reasons. 

You can use your private key to "endorse" somebody else's key 
to allow them to do some particular thing (you have to write a 
short note that says what) that involves you, or check someone 
else's key to see if it's one that you've endorsed.  If you've 
endorsed it, you get back the short note that you wrote, telling 
you what purpose you've endorsed it for. 

Anybody who's endorsed a key can prove that they've endorsed it 
by publishing their endorsement.  You can read and verify public 
endorsements using the public keys of the involved parties.

And you can revoke your endorsement of any particular key, at any
time, for any reason.  The action won't affect other endorsements
of the same key, nor other endorsements you've made.

Finally, you can use your private key to prepare a revocation, 
which can be held indefinitely in some backup storage, insurance
database, or safe-deposit box. If you ever lose your private key, 
you send the revocation and everybody who has endorsed your 
public key gets notified that it's no good anymore.

I think this model is simple enough to be understood by 
ordinary people.  It's also clear enough in its semantics to 
be implemented in a straightforward way.  Is it applicable 
to the things we want to use a PKI for?

				Bear


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