Analysis and Design on Key Updating Policies for Satellite Networks

Satellite networks are becoming increasingly important because of the exciting global communication services they provide. Key management policies have been successfully deployed in terrestrial networks to guarantee the information security. However, long propagation, storage and computation constraints bring new challenges in designing efficient and cost-effective key updating policies for satellite networks. Based on the structure and communication features of satellite networks, a dynamic key management model for satellite networks (DKM-SN) is presented, which includes certificates owned by each satellite, primary keys and session keys both of which are shared between two satellites. Furthermore, a protocol is designed for updating certificates for satellites; different policies for updating primary and session keys are studied and their efficiency and security are analyzed and compared. In addition, simulation environment for satellite networks is built and the key updating processes are implemented in Walker constellation. From the simulation results, further contrasts on key updating time and storage costs between the applications of IBM hybrid key management model (HKMM) and DKM-SN in satellite networks are presented. Finally, important suggestions in designing key updating policies are given