Efficient Revocable Key-Policy Attribute Based Encryption with Full Security

In this paper, an efficient and fully secure revocable key policy ABE scheme is proposed. In our scheme, each user is assigned a key according to its attributes and unique identity. A sender can specify the list of revoked users and attributes of the cipher text explicitly. If the users have been revoked, they can not decrypt the message no matter whether their attributes satisfies the access formula or they combine their keys. The security of the proposed scheme can be reduced to three static intractable complexity assumptions through dual system encryption approach in the fully secure model. Comparing with the existing schemes, our scheme enjoys high security level and efficiency simultaneously.