Research On Aggravate Signature Scheme Withforward Security

As one of the core techniques of modern cryptography,digital signature has been widely used in the field of information security.But in the network security system,the key leakage and the computational cost have become the biggest obstacle to the development of digital signature technology,and it is the focus of this paper to study the digital signature scheme which can not only guarantee the key security but also reduce the operation cost.The digital signature system with forward security is an important technology to guarantee the key leakage.Its rationale is to divide the validity period of the signature key into different time periods,at the end of each time period,the signer uses the key of the current period to compute the new key for the next period in a one-way mode while securely deleting the key that is no longer in use,at the same time,the public key does not change throughout the lifetime of the key.So even if an adversary grasps the signature key value of the current time period,it is impossible to obtain any information about the signature key of the previous time period,which can effectively reduce the risk of key compromise.In the aspect of computational cost,as a kind of "batch processing" and "compression" technology in digital signature field,the aggregation signature can greatly reduce the storage space of the signature and decrease the requirement of network bandwidth.Aggregation signatures can also simplify the verification of any multiple signatures to a single verification,which greatly reduces the workload of signature verification.This paper mainly studies the forward security of the aggregation signature scheme,the main content is as follows:First,based on bilinear pair technique,elliptic curve discrete logarithm problem and strong RSA hypothesis,two new methods of aggregation digital signature with forward security are proposed.The scheme has the following characteristics: It has the non-repudiation,realizes the mutual authentication between the key generation center and the user.The scheme is resistant to existence forgery.With forward security,based on strong RSA hypothesis,the forward security of signature information is realized,and the security of the system is further ensured.Second,a new identity-based proxy aggregation signature scheme with forward security is proposed,which is based on the previous aggregation signature scheme,based on the strong RSA hypothesis,the forward security of the scheme is realized,and finally it proves that the scheme is resistant to existence forgery under the random oracle model and the computational Diffie-Hellman difficult hypothesis.