Research On Satellite Network Routing Algorithm Based On SDN

Satellite network is a kind of network with wide area coverage and multiple application scenarios.However,due to the characteristics of satellite network,such as fast network topology change,large end-to-end delay,and limited on-board storage and processing capacity,traditional ground network routing technology is not fully applicable in satellite network.So solving the routing technology problem in satellite network has become a key problem in the current research and exploration of satellite network.Software defined network is a new network architecture based on the separation of control plane and data plane.It calculates and controls routing paths through the control plane,forwards and processes data packets through the data plane,adapts flexibly to the topological structure and changes of satellite network,improves the routing efficiency and reliability of network,and provides a new way to solve the problem of satellite network.1)Thesis first proposes a satellite network architecture based on software defined network framework.The architecture consists of a ground network control center and three Earth GEO satellites to form a control plane and master the global network topology.LEO satellite,as the data forwarding plane,only needs to complete the data forwarding task,while GEO satellite node activates the interlayer link with LEO to carry out data transmission when meeting the conditions.This architecture reduces the pressure of LEO satellite plane calculation and data storage.At the same time,the SDN controller can obtain network topology information in real time,so that it can flexibly formulate routing and forwarding strategies,greatly improving the flexibility of the algorithm.2)Based on the satellite network architecture based on SDN and the idea of virtual node,thesis proposes a satellite network routing algorithm based on SDN.The global network topology is mastered by the SDN control plane.According to the real-time topology of network nodes,the minimum hop rectangle range is divided according to the logical addresses of source and destination nodes of data packets to obtain the minimum hop path set.Calculate the path weights that meet the requirements of different packet types in the minimum hop set.At the same time,when the network is congested,the path is selected to determine whether the link transmission conditions between LEO and GEO are met.If the conditions are met,the inter-layer link ISL is activated to complete data transmission.The experimental results show that the algorithm can alleviate the degree of link congestion to some extent,reduce the transmission delay of data packets between source and destination satellite nodes,reasonably guarantee the balance between different indexes of the SDN integrated network,and meet the diverse Qo S requirements of users.