Sun Ya Publicaions (Hong Kong) Ltd
A digital signature is one of the most important security primitives in modern cryptography. In a traditional public key signature scheme, methods to guarantee the authenticity of a public key are required, since the public key of the signer is actually a type of random string. To provide the binding between a signer and his public key, the traditional public key signature uses a certificate that is a digitally signed statement issued by the CA (Certification Authority). The need for Public Key Infrastructure (PKI) supporting certificates is considered the main difficulty in the deployment and management of public key signature schemes.