Research On Network Resource Orchestrating Algorithm Based On Virtualization Technology

With the continuous development of communication technology and people’s increasing demand for network services,the fifth generation(5G)mobile communication will greatly expand the capability of mobile networks.The characteristics of 5G network are diversified scenarios,flexible deployment and dynamic demand.Based on Software Defined Network(SDN)and Network Functions Virtualization(NFV)technologies,5G networks can be divided into multiple network slices,each of which is logically independent.To achieve the best experience for a particular type of service,resources can be shared between different services and slice networks.Each network slice is logically a self-contained network,each service has an independent network slice.Multiple parallel network slices can also be deployed on a single physical facility,with each slice providing ultrareliable and ultra-real-time connectivity.In 5G virtualization technology,service function chains(SFC)help automate the scheduling of traffic and optimal routing paths between services in a virtual network,which greatly optimizes the use of network resources and increases control over the network.Therefore,in 5G network slice,reasonable SFC resource arrangement algorithm can help operators to better provide network services to different tenants and users in 5G multi-tenant infrastructure.This paper mainly proposes a solution to the resource allocation problem under the three scenarios of 5G bearer network,access network and core network.Reasonably schedules the virtual resources in the network service function chain,and optimizes them from the perspectives of total user utility,total system energy consumption and total dispatching cost.First,based on the SBA architecture of 5G core network,aiming at the scheduling problems of various service resources in SFC,the server nodes and links in the network are modeled,and factors such as slice type,tolerance delay and node load are fully considered.The optimization problem of resource scheduling is transformed into a joint optimization problem that minimizes the end-to-end delay and the resource scheduling cost of VNFs.This paper proposes a multi-strategy service resource scheduling algorithm based on Viterbi,which not only includes deployment,expansion,and direct scheduling,but also constructs a logical directed graph under the current network model based on hidden Markov chain model to calculate the optimal solution that can minimize the cost-of-service scheduling.The former can adapt to different scheduling scenarios and select candidate nodes,and the latter can finally output the optimal scheduling path of the service function chain.The experimental results show that,compared with GLL and RD algorithms,the total service scheduling cost and resource load rate of each node in the network are significantly reduced,and the average resource occupation cost and average processing delay of nodes are optimized.Secondly,based on the DU/CU separation architecture under 5G NG-RAN architecture,the resource orchestration problem after service function chain deployment is transformed into a VNF migration problem that minimizes system energy consumption.In this process,the energy consumption of the bottom layer of the network and each node is modeled,and factors such as resource type,tolerance delay and migration loss are fully considered.An energy-Aware VNF Instance orchestration algorithm is proposed,which consists of two core modules:VNF integration modul and destination node selection module.The former selects the VNF to be migrated according to the policy,considers the nodes with high and low load rates,and invokes the destination node selection module with the migrate VNF set as the input.The experimental results show that,compared with LUPE and DWRS algorithms,the total energy consumption of nodes in the network and the VNF migration loss caused by the arrangement process are significantly reduced.In addition,this method improves network resource utilization to some extent,reduces the number of enabled nodes,and lightens cluster management.Finally,based on the three-tier architecture composed of SDN controller layer,network function virtualization layer and physical underlying computing resource layer,user-centric framework that maximizes user utility is proposed to solve the resource allocation problem of service function chain deployment.The optimization problem of resource scheduling is transformed into the problem of maximizing user’s utility through the model of aggregation of multicriteria utility theory.An active acceptance control algorithm based on request priority and user preference is proposed,which includes two stages:prediction based on the previous network state,and active control based on utilization.According to the utilization rate predicted by the future state,the controller makes the corresponding decision to the SFC request and issues the control instruction.Based on this,VNF occupies the underlying resources held by the physical node to achieve the purpose of active control and utility maximization.The simulation results compared with FCFS and MSJF algorithms show that the acceptance rate of high-priority requests and the overall user’s utility benefit are significantly improved in the congested network scenario.