An efficient dynamic fine grained access control scheme for secure data access in cloud networks

To assign access privilege for a particular authorized user without disclosing his/her identity for accessing the relevant information and protecting sensitive information from unauthorized access, fine-grained access control for cloud networks is very much essential. Recently many fine grained access control schemes for cloud environments have been proposed in literature using a promising cryptographic solution called attribute-based encryption (ABE). But in a real time scenario, most of them inevitably suffer from lots of serious drawbacks as they are incapable to fulfil some essential security, performance and functionality requirements like user anonymity, users revocation, attributes revocation and user collusion resilience. Moreover these schemes use asymmetric key encryptions which required higher computational cost. In this paper, we present an efficient and secure fine grained access control scheme applicable for cloud networks using symmetric key encryption. Our scheme is able to fulfil fine-grained access control over any type of cloud networks and also ensures that any particular legitimate user can access only that information for which he/she is permitted to access them without compromising user identity. The proposed scheme is resilient against most of all strong attacks such as replay attack and user collusion resilience attack. Moreover our scheme has the provision for user and attributes revocation efficiently. Furthermore, our proposed scheme is light-weight because it uses symmetric key encryption and decryption algorithms. Finally we have shown that our scheme requires lower computation costs and provides higher security compare to other related schemes.