Design And Simulation Of The Space Network Security Routing

Space network is a kind of intergrated space-ground network system,which is composed of multiplicate satellites and near space aircrafts those are deployed in different orbits and connected together with the corresponding ground facilities through the UDLs or the ISLs.Space network can get the real-time information as widely as possible with the minimum cost,and has become the indispensable and significant system in all respects especially in military applications fields.And as a core part of the space network,due to its character of long span space structure,open channel and constrained resources etc,satellite network has high security requirements.Therefore,in order to securely transmit information in space network,it is necessary to ensure reliable routing path in satellite network.Based on the above analysis,the thesis focuses on the satellite network secure routing problems of space network,and obtained the following results:(1)Taking the ease of implementation of satellite networking and the elementary conditions of constellation coverage and visibility into consideration,a two-layered satellite network architecture is proposed,which is composed of LEO and MEO satellite layers.And through modeling and simulation with STK,it is proved that the proposed satellite network meet the requirements of continuous global coverage with less number of orbits and satellites.(2)Considering the reliability of routing path in satellite network,a trustful routing algorithm which operates on a two-layered satellite network consisting of LEO and MEO satellites is proposed.To make the routing path reliable,it first builds a trusted network topology by the approach of trust-evaluation before calculate the routing table.And in order to reduce the deployment costs and communication overhead,all the LEO satellites are equipped without computing power.Meanwhile the ground control center will be used to calculate all the network topologies in advance for MEO satellites in this algorithm,while it sets up a limited number of transmitted snapshots,for the purpose of reducing the computational burden of all of the satellites in MEO layer and their respective storage overhead.(3)The proposed algorithm(TRA)is implemented based on NS2,and is compared with theoptimal routing algorithm and the SGRP algorithm.Results show that in low traffic areas,the TRA and the SGRP has less diffrence,while in high traffic areas,the end-to-end delay performance of TRA is better than SGRP,although the optimal routing is the best.