Research On Resource Allocation Strategy Based On Software-Defined Of Time And Wavelength Division Multiplexed Passive Optical Network

With the sharply increasing number of optical access network users and multimedia services,the time division multiplexed passive optical network(TDM-PON)is more and more difficult to satisfy the demand of users for high bandwidth because of its limited bandwidth capacity.And time and wavelength division multiplexed passive optical network(TWDM-PON),which has the characteristics of low cost,large capacity,long distance and wide coverage,has become a most popular solution of the next generation of passive optical network.However,due to the large number of terminal equipment and the complex process of resource allocation in TWDM-PON,it is hard to be flexibly controlled.In order to strengthen the centralized control and flexible scheduling of TWDM-PON global resources,the software defined network is introduced and the software-defined optical access network(SDOAN)is built.Under the framework of SDOAN,the network resources can be concentratively and efficiently allocated from a global perspective,so the goal of efficient use of resources is achieved.Due to the lack of global centralized control and flexible allocation of inter-TWDM-PONs network resource,the architecture of software-defined optical access network is established and a novel global resource allocation strategy with predicting is proposed in this paper.Based on software-defined optical access network,the fuzzy neural network predicting model is utilized to reduce the interactive information delay between controller and OLT.Simultaneously,the adaptive and flexible weighting is utilized to allocate inter-OLTs resource.Furthermore,an allocation algorithm with filling idle slots is designed to further reduce network delay for intra-OLT resource.The simulation results show that the proposed strategy can optimize allocation of the different layers resource from global network view.Simultaneously,the overall network delay is effectively reduced,and the utilization of channel resources is improved.Due to the lack of cooperative scheduling between OLTs and the different requirements of user for quality of service in TWDM-PONs,a resource allocation strategy with differentiated services based on software-defined is proposed in this paper.The different TWDM-PONs resource has been shared together by building the SDOAN;A differentiated resource allocation scheme is adopted for different priority services and the idle slot between cycles are decreased by ONU sliding request information window according to the different network loads;Simultaneously,to solve the problem of wavelength scheduling in TWDM-PON,the wavelength scheduling mechanism with load balancing is adopted to achieve multi-wavelength load balancing.The simulation results show that the proposed strategy can effectively avoid the waste of resource among TWDM-PONs and the utilization of channel resources is improved,and the requirements of different users for QoS are satisfied.