From: "Rev. Ben" <samman-ben@CS.YALE.EDU>
Date: Fri, 16 Feb 1996 05:05:21 +0800
To: cypherpunks <cypherpunks@toad.com>
Subject: Re: anonymous age credentials, sharing of
In-Reply-To: <Pine.SUN.3.91.960214143233.28807O-100000@viper.law.miami.edu>
Message-ID: <Pine.A32.3.91.960215110839.17030H-100000@FROG.ZOO2.CS.YALE.EDU>
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On Wed, 14 Feb 1996, Michael Froomkin wrote:

> Suppose Alice is a CA who issues anonymous age credentials.
> Bob is 15
> Carol is 25
[...]
> What can stop Bob and Carol from subverting a scheme that relies on 
> anonymous age creditials in this manner?

Transfer of credentials is a big problem in terms of computer based 
authentication.

Authentication is traditionally carried out in one of three forms:

*	Authentication by knowledge(passwords)
*	Authentication by posession(key cards)
*	Authentication by being(biometrics)

With the first two, which are overwhelmingly popular and cheap, the 
transfer of credentials is trivial.

Even if they're not anonymous credentials, the fact that I can hand 
someone my driver's licence to swipe through a card reader next to a 
machine is a simple example of transfer of credentials problem.

Ben.
____
Ben Samman..............................................samman@cs.yale.edu
"If what Proust says is true, that happiness is the absence of fever, then
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