Abstract: In several distributed systems using a certain set of attributes, a user should only be able to access data. Currently, the only method for enforcing such policies is to employ a trusted server to store the data. To keep the shared data confidential against any kind of misuse, a natural way is to store only the encrypted data in a cloud. The key problems of this approach include establishing access control for the encrypted data. Previous Attribute - Based Encryption systems used attributes to describe the encrypted data. While in our system attributes are used to describe a user’s credentials, and encrypting data determines a policy for who can decrypt.