Research And Application Of Digital Signature In Cloud Computing

Cloud computing provides a scalable, powerful computing platform for on-demand services, at the same time it is also facing a number of security threats, the main problem is that the owner of the file stores sensitive data in the cloud. In cloud computing, users usually use a variety of terminal equipment to obtain cloud services, and as the low-end devices are easily lost, computing power is relatively weak and the network is vulnerable to attack, the end-user security has some special problems related to cryptography, such as resource-constrained terminal device, the protection of user’s personally identity information. The thesis focuses on the study of signature theories related to cloud computing.For the user’s personal identity information protection, this thesis uses Boneh-Boyen signature to construct a Slight homomorphic signature scheme, which can achieve identity authentication under the cloud computing and could protcet user’s personally identity information. At the same time,it has a smaller amount of computation, and the thesis gives the verification of the security of the algorithm. For the problem of limited resources in smart terminal equipment, the thesis designs a secure server-assisted verification proxy re-signature scheme according to the unidirectional proxy signature proposed by Ateniese. It takes advantage of the computing power of cloud server to supporting calculations and greatly reduces the calculation amount of the user.The thesis analyzes the security and calculation of the designed program in detail,and programs the designed signature algorithm under linux operating system. It analyzes relevant statistical data through simulation, and prove that the program we have designed has the advantage in reducing the calculation amount of the client. Thus it indicates the program is feasible in the cloud computing.