Research On Energy-saving Technology Of Broadband Optical Access Convergence Network Based On SDN And NFV

With the development of the Internet,the emergence of a large number of emerging services has prompted the access network to evolve toward higher speeds,longer transmission distances,and larger split ratios.The boundaries between metropolitan area networks and access networks have become less distinct.The convergence link and the access link technologies are integrated and the functions are integrated to form a new access aggregation network.It is foreseeable that the energy consumption of broadband access aggregation networks will continue to increase in the future,and a stable annual growth rate will be formed.The global problems such as energy crisis,greenhouse effect and environmental pollution will also become increasingly prominent.Therefore,designing an energy-efficient broadband access aggregation network has become the focus of academic and industrial research.Faced with the dual pressures of service quality requirements and energy consumption conflicts in the next generation access aggregation network.This paper combines software defined network(Software Defined Netwrok,SDN)and Network Function Virtualization(NFV)technology to design and research the network structure and energy saving scheme of optical access aggregation network to realize access aggregation network.Resource sharing isolation,centralized intelligent management and control,and thus optimize resource optimization of the entire network.The main work and achievements are as follows:1)Aiming at the challenges faced by the existing access aggregation network,combined with the upward shift/pooling trend of the optical line terminal(OLT)in the future access aggregation network,this paper designs an OLT/NFV-based OLT pool idea.Time and Wavelength Division Multiplexed-PON(TWDM-PON)network structure,and communication flow between network components.2)Faced with the characteristics of multi-service convergence access aggregation and network centralized management and control under the new architecture,this paper proposes an energy-saving algorithm based on virtual OLT migration.Under the premise of guaranteeing service QoS,the algorithm concentrates the service on as few OLTs as possible through the virtual OLT migration mechanism,and tries not to wake up the OLT in the sleep state to extend the sleep time.The simulation results show that the algorithm can effectively reduce the number of active OLTs in the virtual resource pool,thus saving more energy.3)Aiming at the characteristics of service autocorrelation and long similarity in the access aggregation network,an early sleep-wake energy-saving algorithm based on LSTM traffic prediction is proposed.Traffic prediction and energy-saving control modules are introduced in the SDN controller to predict network traffic.To guide energy conservation.The algorithm enables the OLT and the ONU to fully utilize the data receiving/transmitting gap to sleep to save energy,and complete the sleep-wake state switching before the next polling,thereby reducing the delay performance degradation caused by the activation time,and ensuring Business delay.The simulation results show that the algorithm can accurately predict the network traffic,and can effectively reduce the system energy consumption while taking into account the delay performance.