Routing for predictable Multi-Layered Satellite Networks

Multi-Layered Satellite Network (MLSN), especially LEO/MEO satellite network, consisting of low and medium earth orbit satellites, is capable of providing higher coverage and better service than single-layered one. Its performance in deployment, however, is mainly encumbered by obsolete routing protocols and algorithms. This paper takes the predictability of satellite movements into consideration, based on which a novel routing protocol Predictable Satellite Network Routing Protocol (PSNRP)—is proposed. In this protocol, every topology change due to satellite movement is either described as a predictable or an unpredictable change. On the basis of PSNRP, we import a heuristic routing algorithm for satisfying Quality-of-Service (QoS) requirements from network users, which is convinced as a Non-deterministic Polynomial Complete problem. The QoS requirements in this paper mainly refer to end-to-end delay, bandwidth and package loss rate. In addition to obtaining better routing performance, PSNRP successfully allocates calculation tasks evenly among all nodes, separates user data from protocol control data and achieves stronger robustness against satellite failures and link congestions. The superiority of our routing scheme is proved by simulation results.