Other Directory Sites: SeekWonder | Directory Owners Forum
The following archive was created by hippie-mail 7.98617-22 on Sat Apr 10 1999 - 01:18:50
James A. Donald (jamesd@echeque.com)
Tue, 09 Mar 1999 21:34:15 -0800
--
At 08:17 PM 3/9/99 -0800, Lucky Green wrote:
> IMHO, it doesn't matter who can verify a signature for it
> to be a signature. See Chaum's undeniable signatures. If
> there is any party at all that can verify the signature,
> even if verification is limited to the signer, the
> signature is still a signature.
I am not a lawyer, nor do I play one on TV, but Chaum's
patent on blinded undeniable signatures
<http://www.patents.ibm.com/details?pn10=US04947430> contains
the following words:
The validity of such signatures is based on public
keys [...]
What is claimed is:
[....] using a private key corresponding to a
public key, [...]
[...] a valid undeniable signature
corresponding both to said public key and to
said unsigned message [...]
David Wagner's tokens can only be checked with the private key. There is
no relevant public key that plays any role in the protocol, thus Chaum's
patent on undeniable signatures appears irrelevant.
I have found no patent can plausibly be construed as covering unlinkable
tokens that do not employ public keys.
This does not mean that no such patent exists, but so far no one has given
me a lead to any such patent.
--digsig
James A. Donald
6YeGpsZR+nOTh/cGwvITnSR3TdzclVpR0+pr3YYQdkG
ZA2KaIs+si59WIxAH7kE50hEL+1ec93wELMPQdGL
4CiPbnvrqenB/5qOR+AU+z/bU9cZ8rzHVk7pC0YXJ
-----------------------------------------------------
We have the right to defend ourselves and our property, because
of the kind of animals that we are. True law derives from this
right, not from the arbitrary power of the omnipotent state.
http://www.jim.com/jamesd/ James A. Donald
The following archive was created by hippie-mail 7.98617-22 on Sat Apr 10 1999 - 01:18:50