Research On Intelligent Orchestrating Technology Of Service Function Chain In Optical Network

The continuous generation of new services and the improvement of users’ requirements for network service quality pose bring new challenges to the network of carrying capacity and service orchestration capacity.Software Defined Optical Network(SDON)and Network Function Virtualization(NFV)technologies make network management and service orchestration more intelligent and flexible.It is an inevitable trend to adapt to the complex service scenarios of the future communication network effectively and dynamically perceive the state of the optical network and regulate the optical network resources in advance,which can lay a solid foundation for meeting higher quality and differentiated service needs.At the same time,new services have brought highly diversified QoS requirements and network functional requirements,there is an urgent need for a more flexible and customized service orchestration form.Therefore,the intelligent orchestration technology of optical network service chain has great research significance and application requirements.Compared to general optical networks,large-scale metropolitan area networks have greater service throughput and significant tidal traffic characteristics,which poses higher requirements and challenges for the carrying capacity,resource management,control and scheduling capabilities,and service orchestration of optical networks.To achieve intelligent scheduling of optical network service function chains in largescale metropolitan area networks,it is first necessary to predict tidal traffic in metropolitan area networks.The predicted results can provide the SDON control layer with prerequisite information for real-time and dynamic scheduling of optical network resources.Secondly,generate customized service function chains for different services and optimize its performance through VNF migration algorithms,such as reducing SFC latency,improving virtual resource utilization,and reducing bandwidth resource consumption.Finally,a service function chain reconfiguration algorithm for failed services is proposed to recover failed services.The main innovations of this paper are as follows:(1)A Tidal Traffic Prediction Model Based on LSTM for MAN:A tidal traffic prediction model based on LSTM for MAN is proposed and designed to realize fast and accurate traffic prediction.The prediction result is stable to more than 90%,which can provide effective prerequisite information to schedule network resources and provide more reliable physical network to orchestrating service function chain by scheduling and controlling physical layer resources in advance.(2)Low Latency Service Function Chain Orchestration and VNF Migration Integrated Algorithm:A low latency service chain orchestration and VNF migration integration algorithm is proposed,which can significantly reduce service chain latency.Traditional service chain orchestration algorithms believe that the network functions required by a service chain can only be linked in a specific order.However,VNFs have different independentdependency relationships,and the order of VNFs in the service chain is not unique or fixed.Therefore,this algorithm first determines the independent-dependency relationship between VNFs and generates a service function chain’s VNF relationship matrix and SFC generation matrix,and then generates the optimal service chain with the shortest delay through quasi mapping.Subsequently,VNF real-time dynamic migration is performed for the optimal service chain to further shorten the latency after service chain mapping.Simulation results show that the proposed algorithm can effectively reduce SFC latency.(3)Cost-Efficient Parallel Service Function Chain Reconfiguration Algorithm for Failed Services:A cost-efficient parallel service function chain reconfiguration algorithm for failed services is proposed,which can effectively reduce the resource overhead of packet copying and significantly reduce the latency of SFC at the meanwhile.Firstly,VNFs perform different actions on application packets,so we can identify independent VNFs,and then regenerate the sequential SFC as Para-SFC.Secondly,use light header copying to minimize the copy overhead.Thirdly,we design two microservice compositions to enable the original packet and light header copying packets be transmitted simultaneously on different spectrum part.Simulation results show that this algorithm can effectively reduce the consumption of optical network resources,while significantly reducing the latency of SFC.This research work is of great significance for improving the service quality and the carrying capacity of the entire SDON.