Hierarchical ID-based authenticated key exchange resilient to ephemeral key leakage

Abstract

In real applications of (public key-based) cryptosystems, hierarchical structures are often used to distribute the workload by delegating key generation. However, there is few previous study about such a hierarchical structure in the ID-based authenticated key exchange (AKE) scenario. In this paper, we introduce first hierarchical ID-based AKE resilient to ephemeral secret key leakage. Firstly, we provide a formal security model for hierarchical ID-based AKE. Our model is based on eCK security to guarantee resistance to leakage of ephemeral secret keys. We also propose an eCK secure hierarchical ID-based AKE protocol based on a hierarchical ID-based encryption. © 2010 Springer-Verlag.