Research On Several Issues Of Delay-sensitive Network Based On SDN

The current explosive growth of service demand in the Internet has caused tremendous pressure on service equipment demand and network traffic transmission to network service providers and network infrastructure operators.NFV technology has the characteristics of virtualization and isolation,and SDN technology has a global vision and flexible control characteristics.The combination of these two technologies can effectively alleviate the above pressure.At present,there have been some studies on the deployment of service function chains under the NFV and SDN architectures.This article introduces the research status of the three aspects of SDN / NFV-based network slicing architecture,virtual network mapping,and service function chain deployment.After that,the core ideas and basic architecture of SDN are introduced,and then the standard architecture of NFV,the relationship between NFV and SDN,and the resource allocation problem in NFV environment are introduced.This article mainly studies the deployment of service function chains in core network slices.Aiming at the situation where virtual machine resources in the core network slices have been allocated but VNF has not yet been deployed,the relationship between VNF deployment and offline scheduling of SFC is analyzed.The deployment problem is mathematically modeled,aiming at the optimization goal of minimizing the overall service delay of the core network slice,and a PSO-MCMF heuristic algorithm is proposed to find the deployment problem of the service function chain.Finally,a computer simulation is performed on the algorithm.The simulation results show that the PSO-MCMF algorithm is better than G-MCMF algorithm and R-MCMF algorithm.This article also considers the online scheduling of service function chains in core network slices.For the situation where virtual machine resources in the core network slices have been allocated and VNF functions have been deployed,the description of a virtual machine that can only perform one task at a time the processing process of SFC under the circumstances,after comparing the characteristics of different task queue scheduling schemes,a combined queue scheduling scheme is designed,and then the online scheduling process of SFC is described.The greedy algorithm based on the minimum estimated service delay is used to complete the online SFC Scheduling.Finally,the online scheduling and task queue scheduling of SFC are simulated in OPNET environment.The simulation results show that the combined queue scheduling mechanism proposed in this paper has a lower service delay for high priority tasks than the FCFS queue scheduling mechanism.The average service delay of the service function chain also decreased slightly.