Comment by lxgr
8 hours ago
Blind signatures don’t work like that. Once you unblind them, they are very traceable. Chaumian e-cash can only be spent once for that reason.
8 hours ago
Blind signatures don’t work like that. Once you unblind them, they are very traceable. Chaumian e-cash can only be spent once for that reason.
when you unblind a blind signature all the signer knows is that it's a signature they signed at some point, they know nothing (true zero knowledge) about when or where they signed it among all the other signatures.
Yes, and then you have a signed piece of data that others can verify. How does that help you with preventing duplication of signatures?
E-cash depends on the secrecy of the signed data, and immediate redemption with the issuer once it's been spent/accepted. This is a terrible model for physical cash.