Binary Information Press
Attribute-Based Encryption (ABE) is an effective cryptographic primitive for achieving fine-grained access control of ciphertexts. A well-known concern in the multi-authority ABE setting is that malicious users leak their private keys to construct pirate decryption devices and distribute them to illegal users. To deal with this key abuse problem, the authors introduce the notion of Multi-authority Attribute-Based Traitor Tracing (MABTT), and propose a concrete MABTT scheme. Based on the subgroup decision problem for three primes, the MABTT scheme is proved to be fully secure by using dual system encryption method.