Research On Satellite Network Security And Anti-destruction Strategies

Satellite communication is an important complement to terrestrial communication because of its long communication distance,not restricted by geographical conditions,and not affected by natural disasters.The progress of space technology and the demand of military and commercial have further promoted the development of satellite communication towards network.Satellite network is the infrastructure of a country,but also an important strategic resource.The competition between countries extends from the ground to space.Since the orbital parameters of satellites are public and operate with regularity,they are vulnerable to hard destruction.In addition,satellites are in the open exposed environment and on-star computing and storage resources are relatively tight,vulnerable to network attacks.At present,how to improve satellite network security and anti-destructive capability has become a research hotspot,so the study of satellite network security and anti-destructive strategy is of great significance.Based on the study of satellite network security and anti-destruction,the thesis focuses on the anti-destructive routing,secure access and MEO satellite anti-destruction strategies of satellite networks.(1)In order to solve the problem that the routing algorithm is insensitive to the real-time dynamic changes of the satellite network,a Satellite local network state awareness and adaptive forwarding routing algorithm(LAAR)is proposed.When some satellite nodes are damaged and invalid,the algorithm enables satellite networks to timely perceive the status information exchanged between satellite nodes.In addition,real-time path selection is carried out to avoid the failed node and select a relatively better path during route forwarding,so as to minimize its impact on satellite network efficiency.The performance of LAAR algorithm in terms of probability of selecting better paths and average end-to-end transmission delay is studied in simulation,and the results show that compared with DTDR and ANSR algorithms,LAAR algorithm has lower average end-to-end transmission delay while ensuring higher probability of selecting better paths.(2)In order to solve the problem of computational and storage resource constraint when satellite nodes perform security authentication,Lightweight security authentication method and resource adaptive allocation strategy(LABS)is proposed.Through the core secret value,hash algorithm and random number,the strategy can enable the satellite to carry out identity authentication and key negotiation without storing the ground node information in advance,and it consumes less on-board resources.The strategy classifies the access requests according to their characteristics,allocates computing resources for authentication according to the needs of access nodes,and realizes the balance of satellite network resource consumption.The simulation studies the access failure rate and resource consumption state distribution of satellite nodes when the access requests increase gradually.The results show that,compared with TLSR strategy,the proposed LABS strategy has lower access failure rate and more balanced resource consumption of satellite network nodes.(3)In order to solve the problem that LEO nodes are unmanaged after MEO satellite nodes fail in multi-layer satellite networks,the Anti-destruction strategies for multi-layer satellite networks(SCCA)is proposed.The strategy obtains satellite Node status information(NSI)and Main business features(MBF)of the region through a comprehensive evaluation method.The LEO nodes in the coverage domain of the failed MEO satellites propagate re-access and request information to re-access other satellites in the MEO layer,and other MEO satellites select access paths for the LEO nodes based on NSI and MBF information,which are confirmed by the LEO nodes.Simulations are performed to study the weighted average of the selected re-access paths under random network states,and the results show that the SCCA strategy is able to select better re-access paths compared to the FUTS strategy,and performs better in the case of large differences in network distribution.