Identity-based Strong Designated Verifier Signature Scheme

With the development of networks technology and the wide application of informationtechnology, the information security has become a very important issue in today. The digitalsignature, as one of the crucial components of cryptography, is playing an important role inprotecting the security of communication networks.The cryptography techniques can ensure the enviroment of computer network the confidentiality, integrity, and availability and non-repudiation on the information. It is commonly realized by encryption and digital signature scheme to. Digital signature technology is to provide authentication, integrity and non-repudiation, is one of the core technology of information security. In the designated verifier signature, designat-ed verifier oneself can also produce legal signature, so anyone else will not believe that the signature is legal. Even though others know the undersigned and validation of the designated the private key, also cannot conclude who produces the signature. That is to say, it through sacrifice the undeniable of signature perfect solution to the confict of "secret" and the "real". To allow any third party can not verify the signature, need promote the concept of designated verifier signature to the strong of designated verifier signature. In the public key of traditional cryptography, the entity's identity and public key is usually bind by the public-key ceritificate which presented by the certificate authority (CA CertificaiAuthority). In ID-Based strong designated verifier signature, the public key can verify the signature through their identity instead of by the public key certificate. ID-Based strong designated verifier signature using pairing teachnology has become a of the pop research problems. In this paper mainly studies one of specific digital signature---strong designated verifier digital signature and ID-Based strong Desingated Verifier signature schemes.The main achievements containe-d in this thesis are as follows:(1) The flaws that exist in some existent designated verifier signature schemes are analysed. Typical attack such as deligatability attack is discussed, in which the signer can delegate his(her)sign ability to fixed designated verifier or any third party without disclosing his(her)secret.thereby, any third party created the signature was accepted designated verifier. Through analysing yang's strong multi-designated verifiers Signature scheme, the system had serous defect.(2) Based on the identity of the signature with strong designated-verifier signatu- re combined, two new identity based strong designated-verifier signature scheme are proposed. And the two new scheme were proverd to be security, unforgeability and strong.