Research On Digital Signatures Applied In Fair Exchange Protocol

Digital signatures, one of the most important components of cryptography, are the basic theory for protecting the integrity and authenticity of information. It was applied to key distribution and secure electronic transaction. With the popularity of the Internet, security of Internet becomes more and more important. As one of the ways to solve the problem in electronic transaction, digital signatures are not only necessary but also important to be researched. Digital signatures used in the field of electronic transaction are studied in this paper and the main works are as follows:Firstly, the overview of digital signatures used in the field of electronic transaction is presented, and their ideas and researching states are analyzed respectively. Such as, undeniable signature, confirmer signature, designated verifier signature, verifiably committed signature.A new ID-based chameleon signature from bilinear pairings is proposed, which uses chameleon hash function as a building block. The distinguishing characteristic of chameleon signatures is non-transferable. We combined the chameleon hash function with an ID-based signature scheme to obtain the new scheme, which is both secure and efficient and can be used in electronic auction and electronic voting.A new ID-based concurrent signature scheme is proposed by applied the idea of concurrent signature to a concrete signature scheme. Concurrent signature scheme is actually an economical method for fair exchange of digital signatures. The new scheme satisfied the general model and security requirements of concurrent signature. Since utilizing bilinear pairings, the new scheme has simpler construction and can be a better solution for fair exchange of digital signatures.