In the (t, n) proxy signature scheme, the signature, originally signed by a signer, can be signed by t or more proxy signers out of a proxy group of n members. Recently, an efficie...
Abstract. This paper shows some efficient and provably-secure convertible undeniable signature schemes (with both selective conversion and all conversion), in the standard model an...
Abstract. Group signature schemes allow a group member to anonymously sign on group’s behalf. Moreover, in case of anonymity misuse, a group authority can recover the issuer of a...
We revisit the definition of unforgeability of blind signatures as proposed by Pointcheval and Stern (Journal of Cryptology 2000). Surprisingly, we show that this established de...
In 1994, Harn proposed a signature scheme based on the modified ElGamal's scheme and claimed that the security relies on both of the factorization and the discrete logarithm....