Secure Hierarchical Identity Based Signature and Its Application

Abstract

At EUROCRYPT 2004, Boneh and Boyen [5] proposed a new hierarchical identity-based (ID-based) encryption (HIBE) scheme provably selective-ID secure without random oracles. In this paper we propose a new hierarchical ID-based signature that shares the same system parameters with their hierarchical ID-based encryption scheme (BB-HIBE). BB-HIBE and our signature scheme yield a complete ID-based public key cryptosystem. To the best of the authors’ knowledge, our scheme is the first provably secure hierarchical ID-based signature scheme (HIBS) and is also the first ID-based signature scheme working with the BB-HIBE. The scheme is provably secure against existential forgery for selective-ID, adaptive chosen-message-and-identity attack (EF-sID-CMIA) in the random oracle model, and have a good exact security under adaptive chosen-message attack. As a bonus result, we extend our HIBS scheme into a new forward-secure signature scheme.