Research On Reliability Routing Algorithm Of LEO Satellite Network

The LEO satellite communication system has the advantages of low communication delay,low research and development cost,and flexible communication networking,and has attracted the attention of major aerospace countries.An efficient and reliable inter-satellite routing algorithm is crucial to the performance of satellite networks.However,the current LEO satellite network inter-satellite routing algorithm still has many challenges in terms of reliability: on the one hand,due to the highly dynamic topology changes of the LEO satellite network and the uneven global traffic distribution,the satellite nodes and links are prone to congestion;on the other hand,the satellite nodes and links are prone to congestion;On the one hand,due to the poor stability,openness,and exposure of inter-satellite links,the internal routing of the network is vulnerable to malicious attacks.Therefore,in order to solve the above problems,this article deeply researches the reliability routing algorithm of LEO satellite network.The specific research content is as follows:(1)Aiming at the congestion problem of satellite nodes and links,a reliable routing algorithm of LEO satellite network based on QoS guarantee is proposed.From the perspective of QoS guarantee,this algorithm reduces the probability of congestion of satellite nodes and links,reduces packet loss caused by queue overflow due to congestion,and improves the reliability of routing and forwarding.First,complete network-wide link state database update based on the improved track spokesperson mechanism,and build an optimal routing model with multiple QoS constraints and a balanced distribution of global traffic.Second,topological pruning preprocessing and Lagrangian relaxation technology are used to solve the optimal path.If the optimal path does not exist,a default path is calculated.Then,the obtained optimal path or default path is converted using a compression coding mechanism to obtain a path ID table used to guide the actual routing and forwarding of the data packet.Finally,the simulation test verifies that this algorithm performs well in terms of average end-to-end delay,packet loss rate,throughput,traffic balance index,and normalized link load.(2)Aiming at the potential internal routing attacks in satellite networks,a safe routing algorithm for LEO satellite networks based on node trust is proposed.From the perspective of routing security,the algorithm can detect and isolate malicious nodes in satellite network in time,reduce the impact of malicious packet discarding caused by malicious nodes launching attacks such as black holes and gray holes,and improve the reliability of routing and forwarding.Firstly,a set of dynamic trust evaluation model is constructed by using D-S evidence theory,including the design of direct trust,indirect trust and aggregate trust model.Then,this set of trust evaluation model is used to strengthen the security trust of a low-overhead LEO satellite network routing algorithm based on orbit prediction,and a secure routing algorithm based on node trust degree is designed,including basic routing modules and dynamic trust evaluation processing Module and design of dynamic health diagnosis processing module.Finally,the simulation test verifies that this algorithm performs well in both packet delivery rate and packet loss rate.