BNG Broadband network gateway CFM Connectivity fault management EPON Ethernet passive optical networks FTTB Fiber to the building FTTH Fiber to the home GPON Gigabit-capable passive optical network LLID Logical link identifier MEP Maintenance association end point MIB Management information base MIP Maintenance association intermediate point MPCP Multi-point control protocol MPCPDU MPCP protocol data unit NMS Network management system OAM Operation, administration and maintenance OAMPDU OAM protocol data unit OLT Optical line terminal ONU Optical network unit PON Passive optical networks