CAS-based key management scheme for immeasurable information sharing network

Immeasurable information sharing network (IISN) has been proposed for improving information sharing service in remote rural. How to ensure information security becomes a very important issue for the new network. In this paper, we propose a new conditional access system (CAS) model and a key management scheme for IISN. In the model, we place emphasis on making the CAS more suitable for IISN; we change the traditional two-layer CAS to three-layer CAS based on the architecture of IISN. Besides, we propose a novel 4-level key management scheme for our CAS model. Performance analysis shows that our proposed scheme is highly secure and has outperformance on key management cost.