Certificateless public verification scheme with privacy-preserving and message recovery for dynamic group

Abstract

Public auditing is a topic issue as it makes a third party auditor replace user to verify the data integrity. Hence, it handles users' problems such as cannot be on-line all times and with constrained computing resources. However, this technology may reveal user's information to the verifier. Therefore, privacy-preserving should be considered in public auditing. What's more, the existing public auditing schemes are mainly based on signatures what need to transfer signature and message together. This kind of public verification scheme is not suitable in small bandwidth situation. Especially, due to unstable network, it will be difficult to upload large files and cloud server cannot ensure that the message he gets is correct. Message recovery signature is adaptable in this circumstance as it only transfers signature and the message can be recovered from the corresponding valid signature. Moreover, certificate-based schemes have certificate management problem and ID-based schemes have key escrow problem. To solve above problems, in this paper, we proposed a certificateless privacy-preserving public verification scheme which also supports message recovery and dynamic group. What's more, our scheme eliminates problems of certificates management and key escrow. Furthermore, we show that our scheme is secure and efficient in performance analysis.