Research On Control Protocoland Routing Algorithms Of Software Defined Space-terrestrial Network

With the development of aeronautics and space technology, the space-terrestrial information network plays an important role in the fields of military development, ocean exploration, deep space exploration and so on.The increasing demand of network services also places higher requirements on the space-terrestrial information network. The space-terrestrial information network has the characteristics of fast dynamic change, strong network heterogeneity, long transmission distance, large communication delay and so on. Space nodes are subject to environmental constraints, the weight and size of the more stringent requirements, while the need for scalability of the network.In view of the above-mentioned problems, combining with the idea of software defined network, this paper designs the architecture of the software defined space-terrestrial network. At the same time, we built the simulation platform. It separates the control plane from the transmit plane,satisfying the requirements of size and weight. The controller provides a unified interface to the equipment, and it solves the problems of space-terrestrial information network. In addition, we extend the OpenFlow protocol, and propose two kinds of routing algorithms. Specific work is as follows:Firstly, the architecture of software defined space-terrestrial information network is proposed, and a multi-domain controller and a single-domain controller are used to control the space-terrestrial information network. We regard the terrestrial core network as the backbone network, ground access network and space network respectively as an access network. It is achieved the whole network is control flexibly through the multi-layer control structure.Secondly, based on the software defined space-terrestrial information network architecture, we built simulation platform to achieve the programmable control of the platform. OVS module is designed to provide a unified interface for the devices. In addition, we developed the OpenFlow protocol extension scheme for the OVS module in the space-terrestrial network.Thirdly, two kinds of routing algorithms are proposed, which are multi-path routing strategy and security factor-based routing algorithm,which are based on software defined space-terrestrial information network.The multi-path routing strategy solves the problem of interruption of service caused by satellites’ motion. The security factor-based routing algorithm selects the safest path by changing the path weight to guarantee the reliable transmission of service.