;Anonymous credential systems promise efficient, and ubiquitous access to digital services while preserving user′s privacy. In an anonymous credential system, a user Alice can obtain credentials from an organization, and she can prove to the verifier that she has been given appropriate credentials without revealing any information about her identity. And the technique of zero-knowledge proof is adopted in existing anonymous credential systems to protect the attributes from being known by the verifiers. However, the computation of zero-knowledge proof will increase linearly with the number of attributes. And the existing anonymous credential systems are lake of effective revocation approaches.
In this thesis, an efficient anonymous credential system with revocation is proposed, and the technique of chameleon hash is adopted to replace complex zero-knowledge proof for performance improvement. In addition, we use the concept of group signatures to implement a practical approach of revocation to overcome the disadvantage of existing anonymous credential systems.
