CC-SDSN: A Collaborative Control Plane for Software Defined LEO Satellite Networks

Available control plane designs for Software Defined LEO Satellite Networks (SDSN) suffer from the problems of high network update latency, large flow setup time, and low network throughput. This paper proposes a new collaborative control plane architecture for SDSN (CC-SDSN), which consists of a Network Control Center (NCC) and multiple Ground Relay Stations (GRSs) in the terrestrial networks, as well as multiple Satellite Group Controllers (SGCs) in the LEO satellite networks. Each SGC maintains the local view of a group of LEO satellites and supports the quick intra-group flow setup. The NCC takes advantage of the powerful computation resources in the terres trial nodes to maintain a global view of the whole LEO satellite network and is responsible for the rapid inter-group flow setup, while the GRSs are used to ensure the real-time communication between the NCC and SGCs and thus to reduce the network update latency. The designs of the protocol for handling data f low and synchronization operations in CC-SDSN, and the pre caching scheme for inter-group flow tables are addressed as well. Finally, extensive experiments based on Satellite Tool Kit (STK) and Mininet are conducted to demonstrate the efficiency of CC SDSN in terms of network update latency, flow setup time, and network throughput.