The Application And Reseach Of Improved Digital Signatures Scheme

With the rapid development of computer network technology, information security issues become increasingly prominent. the digital signature technology as one of its technology-based techniques, has been widely used in such areas as military, communication, e-commerce and e-government affairs and so on, and its role can not be replaced of by other technologies in authentication, data integrity, and anti-denial and other aspects. As the electronic signature law is being carried out, this application will become more common.First of all, the article discusses and analyzes the current situation and its future development trend of digital signature. Second, the relations between the cryptology and the digital signature is discussed, including the cryptology and the mathematical foundation of digital signature, the basic concepts related to digital signature, and the arithmetic of hash function applied to the digital signature, the blind signature scheme and so on. Third, the two kinds of digital signatures based on discrete logarithm are deeply analyzed and researched. Through the study about all the attack ways the ElGamal signature and analysis about the security of the DSA digital signature, we found that many problems existed in the original signature and certification programs, such as the low speed, low safety, and so on. Thus improved respectively digital signature programs were put up with. The improved scheme based on DSA used a new type of signature style and verification form. The expression of the signature and verification are not involved seeking multiplicative inverse operation, reducing the computational algorithms to improve the operation of the digital signature system speed. At the same time, by using the DSA algorithm based on prime number domain and its sub-domains to seek the high-security practices of the difficulty of discrete logarithm, and by the SHA-256hash function algorithm, we improve the security of digital signatures. And on this basis, a digital signature system is designed and implemented. The results show that the signature schemes proposed to improve the calculation speed is faster than the original program, and more secure. Last but not the least, the article puts up with the improved and advanced blind signature scheme based on the ElGamal, and the application of digital signatures in the e-cash system and the specific scheme is expounded, analyzed and discussed to a certain degree. Through the analysis and comparison, we can see that the improved blind signature system which is based on the ElGamal is safer and the former information can easily be restored through the blind signature. Through the analyzes and comparison about the function and effect of the cryptonym off line system in e-cash system, we can see that the system is safer, anonymous, and controllably anonymous, and it can not be cost again and can not be fabricated, so we can improve the efficiency greatly.