An access control model for cloud storage using attribute-based encryption

In this work, we present a prototype of multi-user system for access control to datasets stored in a cloud. In the system, each user is assigned a set of attributes that characterize his identity in the system. The encrypted datasets to be shared among users are stored in the cloud, and the access control is provided by cryptographic methods. The basis of the system is multi-authority attribute-based encryption scheme. To improve security, our implementation supports a Certificate Authority, independent of Cloud Service Provider, and signed Revocation Lists. Our prototype can interoperate with existing cloud storage via API. The computational overhead is distributed among a large number of users, instead of assigning them to any particular party.