Research And Implementation Of PON Protection Scheme In GPON

The appearance of the Internet has enriched people's life, shortened the distance, brought great convenience to the public. The Internet includes the core network and access network which is achieved by broadband access technology responsible for connecting the users and the core network. Broadband access technology develops from digital line to fiber, now the Passive Optical Network (PON) technology has been becoming more widely promoted and deployed by operators to provide full service, high bandwidth and high quality service for the users. PON network has a variety of types, and the type of point to multipoint tree structure is used most widely. In order to ensure the PON network survivability, PON protection recovery mechanism is indispensable, otherwise once the trunk fiber failure, all users in the access network will not be able to use the service, causing serious consequences.In this thesis, we study the PON protection mechanism of GPON system, the core idea of this mechanism is to enhance the reliability of GPON system by using redundant backup. Firstly, it introduces the composition of GPON network, and the three core devices in GPON network, including the optical line terminal, the splitter and the optical network unit. This thesis proposes four kinds of protection schemes, after simply analyzing the security, the cost and the difficulty of the deployment of the four schemes, we choose type B PON protection scheme to design and implementation on OLT equipment of Shanghai Bell. In this thesis, the design of type B PON protection scheme contains two parts, the user level and system level, the user level is to provide users with the system interactive commands, mainly for the creation, deletion and query of PON protection group. The system level provides three modules of detection, switching and synchronization to complete the switching process between PON port. This thesis gives the specific implementation process of the PON protection scheme based on the GPON equipment of Bell Company in Shanghai. Finally from the GPON system, improving two points on the PON protection scheme, thus reducing the burden of the system caused by PON protection, strengthening the accuracy of users' service when switching PON protection.Finally, verification and testing have been done on GPON equipment based on Shanghai Bell, including CLI command, break time with the scenes of user forced switching and system automatic switching tested and the MibDataSync mechanism, the effectiveness of PON protection mechanism is judged by the average break time.The results show that the break time of the PON protection scheme meet the standard requirements, and MibDataSync mechanism helps avoid break in a long time, it has a certain business value.