Research On Cross-domain Resource Collaboration And Joint Optimization Strategy Of Satellite-terrestrial Integrated Network Based On Service Function Chain

With the rapid development of communication technology,people have higher and higher requirements for communication services.Although the new generation of communication network technology has greatly improved the quality of communication services,there are still shortcomings in some scenarios such as remote areas and densely populated areas.Therefore,satellite-terrestrial integrated network has gradually become a breakthrough in the development of next-generation communication networks.The satellite-terrestrial integrated network framework based on SDN(Software Defined Network)/NFV(Network Functions Virtualization)technology can effectively overcome the problem of equipment and protocols between satellite networks and terrestrial networks,deeply integrate satellite networks and terrestrial networks,and achieve close integration of satellite terrestrial heterogeneous networks.The service function chain technology based on NFV technology can flexibly configure network resources and apply them to specific network functions,improving the accuracy of network resource scheduling.The focus of this paper is to achieve the resource coordination and joint optimization of satellite network and ground network through the deployment and reconstruction strategy of the service function chain.The research content of this article is divided into the following three parts1.In this paper,a satellite-terrestrial integrated network simulation platform is built based on OPNET software.The simulation platform mainly includes ground transmission nodes,satellite nodes and control nodes.The satellite nodes established inter-satellite links and satellite-toground links by wireless transceivers and antennas.The ground transmission nodes are specifically divided into service source nodes,ground gateway nodes and transmission nodes,which implement service generation and data transmission.As the control center of the network,the control node mainly achieves the calculation of global control and resource allocation strategy.The platform further builds a routing mechanism according to the simulation requirements to complete the simulation content and improve the simulation quality.2.SDN/NFV technology can flexibly control and coordinate network resources,but it lacks a scheduling strategy for network resources.The deployment strategy for a single quality of service can easily cause excessive resource consumption in a certain area,which makes it difficult to provide high-quality services or even services when faced with new requests,resulting in a decrease in service quality and system performance.In response to the above problems,this article proposes a load balancingoriented service function chain deployment algorithm.The algorithm divides the deployment of the service function chain into two steps.The first step uses the tabu search algorithm to complete the search of the service function chain path.The second step The genetic algorithm is used to complete the instantiation of network functions,and finally iteratively realizes the balanced scheduling of link bandwidth resources and node computing resources in the system,and is verified by simulation.The simulation results show that the algorithm can improve the performance of about 20%compared with greed algorithms and traditional genetic algorithm in terms of service request reception.3.The satellite-ground integrated network and the service function chain network is a dynamic network,and changes in the link and resource status occur at all times.A static service function chain deployment strategy under a dynamic network cannot guarantee the best long-term resource allocation and system stability.Therefore,this paper proposes a service function chain reconstruction algorithm to solve the resource optimization problem under a dynamic network.The algorithm reconstructs service functions through joint optimization.Chain selection and reconfiguration service function chain deployment strategy realizes the dynamic maintenance of network resources.In the selection process of reconfiguration service function chain,the algorithm completes the selection of reconfiguration service through the combined action of filters and iterators.In the function chain deployment strategy calculation program,the algorithm first uses the K short path algorithm to calculate multiple paths,and then uses the particle swarm algorithm to complete the instantiation strategy calculation of the virtual network function.At the end of the paper,simulations verify that the proposed algorithm can improve the performance of about 20%compared with greed algorithms and random algorithm in terms of service request reception and bandwidth utilization.