Tim May writes:
> Basically, Chaumian blinding would allow the holder of a credential
> to selectively reveal bits of a credential, like uncovering just
> window of an envelope with many data fields. An age credential could
> be revealed without revealing a meatspace name credential.
>
> (There are issues of biometric authentication to consider, else this
> envelope could be loaned to others, like driver's licenses are for
> getting into bars.)
Right, and this is why all the whining about biometrics is misplaced.
Biometrics are a perfectly reasonable and useful technology. They are
absolutely essential for a world which protects privacy via cryptography.
Biometrics enable is-a-person credentials which can be used to prevent
improper sharing of other credentials. They allow for anonymous credit
ratings, where you can prove that you have paid your debts without
revealing your ID. There are a host of other applications which depend
on people not being able to freely swap credentials and being able to
prove membership in various groups.
Of course it is a long way from here to there. Power-hungry institutions
have little incentive to move away from a world in which people
are increasingly tracked and recorded in every detail. And paranoid
cypherpunks shy away from any system which will add accountability even
when wrapped in a shield of pseudonymity. The result is that there is
little or no market for this technology. The fact that it's patented
up the wazoo doesn't help, either, of course.
