The blinding of weak signatures

Abstract

The linearity of “check vectors” - a technique of secure distributed computation - gives an efficient solution to the problem of blind weak signatures (where a weak signature requires the on-line participation of a third party [IT]). We refine aspects of the notion of “blinding a signature,” and apply our weak schemes to on-line digital cash and other problems. The protocols we present are distinctly short, simple, and of low complexity.