Research On Routing Algorithm Based On Qos Guarantee In Sofa Ware Defined Satellite Networks

Satellite networks have become a research hotspot in recent years due to their advantages of wide coverage,less impact on topography and landforms,and immunity from natural disasters.However,the traditional distributed satellite network routing mechanism requires high on-board processing and switching capabilities,which leads to some problems such as difficult satellite management and complex node design.In addition,with the expansion of the scale and the enhancement of the capability of the satellite network,it will serve more and more services with different quality of service(QoS)requirements.How to provide different QoS guarantees for different services on a unified infrastructure is very important.In view of the above challenges and requirements,this thesis studies the routing algorithm based on QoS guarantee in the software defined satellite network.The main contents are as follows:(1)In view of the shortcomings of the traditional distributed satellite network routing mechanism mentioned above,this thesis introduces Software Defined Networking(SDN)into satellite networks,and proposes two satellite network models according to the difference in the deployment form of the controller nodes:the SDN-based single-layer controller satellite network model and the SDN-based two-layer controller satellite network model.And the model design and interaction process are elaborated in detail.The satellite network models proposed in this thesis decouple and separate the control plane and the data plane.The satellite node as the data plane only needs to implement simple data forwarding,and the functions of satellite management,resource allocation,and routing calculation are handed over to the control plane for unified processing to solve the difficulty of satellite management,complex node design and other issues.(2)In order to meet QoS requirements for different types of services,this thesis proposes a satellite network routing algorithm based on QoS guarantee in view of the satellite network models proposed above.The core design of the algorithm is as follows:Firstly,according to the usage scenarios and characteristics of different services,the services in the satellite network are divided into Class A real-time interactive services,Class B request-response services,and Class C unidirectional data flow services to provide differentiated services;then this thesis proposes a multi-queue scheduling strategy combining priority queues and weighted round-robin queues to provide services with the highest priority for class A services,and services with flexibly configurable weights for class B and class C services;finally,a multi-path routing strategy that supports differentiated services is proposed.For Class A and Class B services,a routing algorithm for latency-sensitive services is proposed to meet the service requirements of low latency and low packet loss rate.For Class C services,a routing algorithm for bandwidth-sensitive services is proposed to meet the highthroughput business requirements.By combining multi-queue scheduling strategy and multi-path routing strategy,this algorithm can guarantee the QoS requirements of different types of services.(3)This thesis builds the network model and simulates the routing algorithm through the satellite network simulation platform.Firstly,based on the satellite network simulation platform,the node modeling of communication nodes is carried out,the message format of communication between nodes is defined,and the network simulation parameters are configured;then,the satellite network routing algorithm based on QoS guarantee is implemented on the simulated satellite network model.The simulation shows that the algorithm can guarantee the QoS requirements of different types of services,and compared with the previously proposed low-complexity routing algorithm,when the global business volume reaches 80Mbps,the average end-to-end delay of the algorithm is reduced by about 43%,and the average Throughput is increased by about 26%,and packet loss rate is decreased by about 33%.