On The Security Of Data Access Control For Multi Authority Cloud Storage Systems

Abstract

Data Access control has becoming a challenging issue in cloud storage systems. Some technique have been proposed to achieve the secure data access control in semi trusted cloud storage system. Recently, K. Yang et al. proposed a basic access control scheme for multi authority cloud storage system (DAC-MAC) and an extensive data access control scheme (EDAC-MACS). We claimed that the DAC-MACS cloud achieve efficient decryption and immediate revocation and the EDACMACS could achieve these goals even though no revoked users reveals their key Update keys to the revoked user. However, though our cryptanalysis, the revocation security of both schemes cannot be guaranteed.