Abstract: To key management scheme based on symmetrical cryptographic system, it is crucial to get balance of securi- ty and performance. According to satellite network nodes resource constraints, a key elements distribution method was introduced based on random matrix for nodes. It simplified the construction of key rings, and can make sure that any node can establish different session keys with different other nodes. Then we gave the corresponding key update mecha- nism The simulation results show that this method can guarantee security and reduce storage and computing cost by keys significantly at the same time.

Key words: Satellite network, Key management, Symmetric key, Sequent snapshots topology, Clustering