Identity based broadcast encryption with group of prime order

Abstract EN

Identity Based Broadcast Encryption (IBBE) is a cryptographic primitive, which allows a center to transmit encrypted data over a broadcast channel to a large number of users such that only a select subset of privileged users can decrypt it.

In this paper, based on bilinear groups, we propose a secure IBBE scheme with a constant-size system parameters, private keys and ciphertexts.

This construction uses dual pairing vector space technique in prime order groups, which can simulate the canceling and parameter hiding properties of composite order groups.

Furthermore, we show that the proposed scheme utilizes a nested dual system encryption argument to prove full secure (adaptive secure) under the Decisional Linear assumption (DLIN) (static, non q-based) in the standard model.

To the best ofour knowledge, our scheme is the first provably secure IBBE scheme in the literature to achieve this security level.