Research On Resource Scheduling In Satellite Internet With Slicing Technology

With the rapid development of mobile communication technology,large-scale Internet of Things,streaming media and other business types continue to emerge.The rapid growth of mobile data traffic and the demand for global seamless access put forward higher requirements for the ground communication network,which requires the network to have stronger robustness and the ability of global random access.The development of satellite communication technology provides new solutions to the above challenges.Satellite networks have the characteristics of wide coverage and are not constrained by geographical environment,which can play a complementary role in the ground communication network.Applying network function virtualization and slicing technology to satellite networks can achieve unified management of satellite communication network resources and provide end-to-end services across multiple network domains.It can also improve the flexibility of services and enhance the ability of satellite network services.Different from terrestrial networks,the satellite network is highly dynamic,the network space-time span is large,and the onboard load resources are limited,so the management and scheduling of network slices,network function mapping,and resource reallocation are more complicated.In order to realize the reliable service and effective utilization of resources for satellite network slicing,on the one hand,it is necessary to give full play to the advantages of network slicing technology,and on the other hand,it is necessary to minimize the impact of discontinuous slicing service caused by the dynamic nature of satellite network.Therefore,it is of great significance to design the satellite Internet management architecture based on slicing technology and the slicing resource scheduling strategy of satellite network for multiple services.Based on software-defined architecture and network function virtualization technology,the research and innovation of resource scheduling strategy for satellite Internet slicing are focused.Firstly,for the multi-service scenario of satellite Internet,a resource management architecture based on slicing technology is proposed.The resource scheduling strategy for satellite access network slice is designed and modeled.The sum of slice QoS,system spectrum efficiency and service acceptance rate is taken as the system utility,which is taken as the optimization objective.A multi-service slice resource scheduling algorithm(SA-MS)based on simulated annealing is designed,which allocates resources for different types of service slices according to the user slicing request information,and then allocates RB resources for users of each service slice based on the polling scheduling algorithm.The simulation analysis shows that when the attenuation coefficient is 0.95,the SA-MS algorithm has the best performance and higher system utility,which not only guarantees the quality of service of various slices,but also improves the system spectrum efficiency.Secondly,considering the long transmission distance of satellite network and the unstable link quality at this stage,it is difficult to ensure the quality of data transmission,so it is necessary to further study the reliable mapping scheme of satellite end-to-end network slicing service function.First,the deployment path reliability model is constructed by integrating the computing resource load of network nodes,network topology connection and the occupancy of link bandwidth.Subsequently,a slice mapping algorithm based on reliability awareness(RA-SMA)is designed.The virtual network function sequence is generated based on user request information,and then mapped to the path with the highest reliability.Finally,the comparison between RA-SMA and the delay-based slice mapping algorithm(SPO)proves that RA-SMA solves the reliable mapping problem of satellite network slices,and the node resource utilization rate and link resource utilization rate are increased by 28.4%and 41.9%,and the service acceptance rate is increased by 19.7%.Thirdly,in order to solve the problems of link connection interruption and slicing reconfiguration caused by the high-speed movement of LEO satellites,a cost-based satellite Internet slicing reconfiguration strategy is proposed.First,considering the cost and delay of node and link migration in the slice,the cost model of slice reconfiguration is constructed.Then a slice reconfiguration algorithm based on lowest cost(LC-SRA)is designed.The slice link disconnection ratio predicted by the ground controller is used as the condition to judge.When the link disconnection ratio is less than the threshold value,the link migration and node network function remapping scheme with the lowest cost is selected.Otherwise,the reconfiguration method based on reliability awareness is selected.The simulation results show that the optimal threshold of reconfiguration strategy is 1/3.Compared with the slice reconfiguration algorithm based on minimum delay(MD-SRA),the average delay of slice reconfiguration of LC-SRA algorithm is reduced by 14.8%,and the total cost is reduced by 14.6%.