Abstract:

Focused on the Chaum’s RSA-based blind signature scheme and introduced the strong un-forgeability in blind signature, a new class of blind signature schemes called strong blind signature scheme was presented. A conclusion was proposed which the strong blind signature and the unique blind signature were equivalent by using game reduction and comparing the un-forgeable attack game of strong blind signature schemes with that of the unique blind signature schemes. From this conclusion, more general secure definition and determinant methods for the unique blind signature schemes were proposed, so the open problem that how to decide the unique blind signature schemes was solved.

Key words: blind signature; strong un-forge ability; unique blind signature; strong blind signature; one-more-forgery