International Association
for Cryptologic Research

This paper examines whether a revocation function can be added to a protocol, protocol FSU, that has been adopted as an international standard, ISO/IEC11770-3. Protocol FSU is an IB-AKE protocol based on a mathematical problem, an asymmetric gap bilinear Diffie--Hellman (GBDH) problem. To make protocol FSU revocable, a generic technique is applied, which converts an identity-based encryption scheme to a revocable identity-based encryption scheme by introducing a symmetric-key encryption scheme. In addition, to make the converted RIB-AKE protocol efficient, we reduce ephemeral information exchanged in the protocol, and introduce an additional parameter to the master public-key where the secret information of the additional parameter is not needed to include in the master secret-key. We discuss the security of the resultant protocol, and prove that it is rid-eCK secure under the asymmetric GBDH assumption.