With data garage and sharing services in the cloud, users can effortlessly modift and shared a records as a group. To make certain shared data integrity may be verified publicly, users in the group need to compute signatures on all the blocks in shared records. Different blocks in shared information are commonly signed by means of different customers due to records modifications performed by different users. For security reasons, once a consumer is revoked from the group, the blocks which have been previously signed with the aid of this revoked user should be re-signed through an existing consumer. The straight forward technique, which lets in an existing consumer to download the corresponding a part of shared facts and re-sign it throughout user revocation, is inefficient because of the large size of shared datas within the cloud. On this project, we suggest a novel public auditing mechanism for the integrity of shared information with efficient consumer revocation in thoughts. By using using the idea of proxy re-signatures, we permit the cloud to re-sign blocks on behalf of existing customers in the course of user revocation, in order that existing customers do not want to download and re-sign blocks with the aid of themselves. In addition, a public verifier is always able to audit the integrity of shared records with out retrieving the whole information from the cloud, even supposing a few a part of shared records has been re-signed by using the cloud. Moreover, our mechanism is able to help batch auditing by verifying multiple auditing duties simultaneously. Experimental results display that our mechanism can considerably improve the efficiency of user revocation.