A Hierarchical Identity-Based Signature from Composite Order Bilinear Groups

Abstract

Cloud storage has become one of the integral parts of online life. However, the cloud storage brings in new kinds of data security issues as well. Authentication framework for both users and services provides an efficient solution to the security and privacy problems of the cloud storage. In this paper we propose a Hierarchical Identity-Based Signature HIBS scheme using composite order bilinear groups. We present the methodology of dual system signature to prove that our scheme is secure against existential forgery on adaptively chosen message and identity attack under standard model. Our HIBS scheme shares the same system parameters with the hierarchical identity-based encryption LW-HIBE scheme by Lewko and Waters, and it is as efficient as the LW-HIBE. Combining our signature scheme with the LW-HIBE scheme yields a complete solution of an identity-based public key system, which can be utilized to build an authentication framework for cloud storage.