Contributions to privacy-preserving digital signatures and their applications

Digital signature is one of the fundamental cryptographic primitives that are widely used in real applications. It can provide authenticity, integrity and non-repudiation, which are essential security properties in many e-commerce and networking applications. A normal digital signature is publicly veriable. However, in many applications such as e-voting, e-auction and wireless communications, user privacy is another important security property that must be addressed. Therefore, privacypreserving digital signature has been a popular topic in the literature of cryptographic research.