Attribute Based Encryption for Decentralized ...

Attribute Based Encryption for Decentralized Access Control of Data Stored in Cloud

Author Name : Saranya P M

ABSTRACT : In cloud computing, users can outsource their computation and storage to servers using Internet. Access control in clouds is gaining attention because it is important that only authorized users have access to valid service. Care should be taken to ensure access control of sensitive information. Here proposed a new decentralized and distributed access control scheme of data stored in cloud so that only authorized users with valid attributes can access them. Existing work on access control in cloud are centralized in nature. That is they take a centralized approach where a single key distribution centre (KDC) distributes secret keys and attributes to all users. Unfortunately, a single KDC is not only a single point of failure and is difficult to maintain because of the large number of users that are supported in a cloud environment. We, therefore, emphasize that clouds should take a decentralized approach while distributing secret keys and attributes to users. In the proposed scheme, the architecture is decentralized, meaning that there can be several KDCs for key management. Here the cloud verifies the authenticity of the user without knowing the user’s identity before storing data. The system also addresses user revocation. A writer whose attributes and keys have been revoked cannot write back stale information. Thus the proposed scheme is resilient to replay attacks and supports creation, modification, and reading data stored in the cloud. An attribute based signature scheme is used to support anonymous authentication.