Research On Efficient Ring-based Protection Architecture For Time And Wavelength Division Multiplexed Passive Optical Network

With continuous development of new applications such as virtual reality,augmented reality and 4K/8K ultra HD video,high-speed transmission of massive data is applied in many fields of cloud computing,Internet Plus,big data,smart city and so on.The rich business puts forward the requirements of "high flow","high concurrency" and "high awareness" to broadband access network.The TWDM-PON,which has the characteristics of high light ratio,wide coverage and high bandwidth,proves to be the competitive solution for the next generation passive optical network.In order to ensure the stable operation of the network,the survivability of the network can not be ignored.So in this paper,the protection technology of TWDM-PON is researched,and two new protection architectures are proposed.Moreover,the structure of these two architectures and the specific protection measures are explained in detail.Firstly,to solve the problem in most existing TWDM-PON protection architectures such as the small protection range,the excessive protection cost and the lack of network scalability,a TWDM-PON protection architecture with high reliability and flexible extensibility is proposed in this paper.The architecture can provide reliable ring protection scheme against a fiber fault occurring on main ring,sub-ring or last mile ring.Hence,the reliability can be ensured and the protection cost can be reduced at the same time.In addition,the extended node(EN)is used to realize the network expansion smoothly between two adjacent remote nodes(RNs)for the flexible extensibility and the 1:1 protection scheme is applied against the connected fiber fault between RN and EN.Secondly,based on the reliability of the network,the fault influence range is usually larger under fiber fault condition in most existing TWDM-PON protection architectures.Moreover,if the uplink and downlink signal are used as monitoring signal in the process of traffic transmission,it will be difficult to meet the requirement of the failure monitoring of discontinuous business.So a TWDM-PON protection architecture with strong stability and sustainable fault monitoring is proposed in this paper.The architecture has strong stability,which can effectively reduce the influence of network fault range with different fault locations.Moreover,the architecture can provide reliable ring protection scheme against a fiber fault occurring on dual-ring of RN or last mile ring,which reduces the protection cost.In addition,the architecture has high wavelength utilization.The wavelength of the transmitters in OLT can be supplied to more RNs and ONUs through the grouping bidirectional transmission mode.Furthermore,the architecture keeps to monitor the optical fiber fault in real time,which could ensure the accuracy and timeliness of fault recovery.