Science & Engineering Research Support soCiety (SERSC)
In this paper, the authors design a method for efficient revocation within ciphertext-policy attribute-based encryption scheme. Their main technical innovation is based on linear secret sharing and binary tree techniques, every user in system is assigned with both a set of attributes and a unique identifier. Any user can also be efficiently revoked by using this identifier. Furthermore, this technique resulted in two key contributions: the size of the cryptographic key material is smaller and encryption/decryption cannot be affected with an unbounded number of revoked users.