Certificateless Ring Signature Scheme from Anonymous Subsets

Abstract

In a ring signature scheme from anonymous subsets,a member of a setcan freely choose a family of subsets including their own subset tocompute a signature which enjoys two properties: (1) the externalverifier is convinced that all members of some subset in the subsetshave cooperated to compute the signature; (2) he has no informationabout which subset has actually signed the message. Certificatelesspublic key cryptography was first introduced by Al-Riyami andPaterson in Asiacrypt 2003. In certificateless cryptography, it doesnot require the use of certificates to guarantee the authenticity ofusers' public keys. Meanwhile, certificateless cryptography has notthe key escrow problem which exists in the identity-basedcryptography. In this paper, we propose a certificateless ringsignature scheme (CL-Ring) from anonymous subsets.This scheme isprovably secure in the random oracle model.