Research On Virtual Network Embedding Mechanism Based On Network Resource Virtualization And Performance Analysis

In recent years,high-performance Internet applications as big data and cloud computing are emerging.These applications usually have their own resource usage and network access pattern,which requires dedicated network services that can provide specific bit-rate and quality of service(QoS).However,the traditional underlying optical infrastructure is increasingly unable to satisfy the needs of these applications.Therefore,optical network virtualization technology emerged at the right moment.Optical network virtualization technology can provide dedicated virtual optical network request VON for each type of application.Based on the concept of infrastructure as a service(IaaS),VON requests can be constructed for each specific application,and multiple VONs share the same physical infrastructure,including link and node resources in the network,additional data center(DC)resources,and so on.Optical network virtualization technology can provide a resource sharing mechanism for multiple VON requests on the underlying optical infrastructure under the elastic optical network(EON),and ensure the effective utilization of network resources at the same time.This paper studies the mechanism and performance of virtual network mapping based on network resource virtualization.Firstly,a virtual network mapping mechanism based on the energy saving model is proposed.In this mechanism,each switching node of the substrate elastic optical network is configured with a sliceable optical transceiver.An integer linear programming model is formulated to evaluate the performance of the mechanism.Based on the traditional virtual network mapping scheme,the node mapping algorithm which is aware of the effective use of data center energy and the link mapping algorithm which is aware of the effective use of optical transceiver energy are designed,respectively.Secondly,an elastic optical network architecture RvEON based on resource virtualization is proposed.The system consists of three layers,including the infrastructure layer,the control layer and the service layer.It realizes the spectrum virtualization on the physical link and also the virtual vTP of the optical transceiver on the physical node.Each vTP connects the subcarrier resource pool and the modulator resource pool.This architecture can provide an effective and reasonable implementation scheme for network resource virtualization.Then,based on RvEON architecture,a new type of intergrated virtual network mapping mechanism based on RvEON is designed,considering the shortcomings of traditional virtual network mapping mechanism,including ignoring the influence between node mapping and link mapping,subcarrier resources,the number of modulators and the influence of transmission distance.In the first step,the corresponding integer linear programming model is established,which takes into account the subcarrier and modulator resource constraints of the virtualized TPs.In the second step,a novel routing,spectrum,subcarrier and modulator allocation algorithm RMS~2A is designed to establish the optical path and assign network resources for the virtual network request VON by means of virtual auxiliary graph.In the third step,static and dynamic integrated virtual network mapping mechanism are designed for different scenarios,where the node mapping and link mapping are performed in an integrated way,which is totally different from all existing two-phased VONE schemes.Finally,based on the above-mentioned integrated virtual network mapping mechanism,the traditional two-phased virtual network mapping mechanism is used as the benchmark algorithm to compare the difference of the blocking rate between the two mechanisms.The simulation results show that the proposed integrated virtual network mapping mechanism can have better performance in blocking rate.In addition,the effect of the bit rate of VON request and the combination of different modulator types on network performance is also studied.