The PON port is like the main gate on the ONU (Optical Network Unit), connecting it to the Optical Distribution Network (ODN). A passive optical network (PON) or Gigabit Passive Optical Network (GPON) is a point-to-multipoint (P2MP) network that uses a combination of active transmission equipments and passive cable components to provide network connectivity to end user's devices. In practice, PONs are typically used for the last mile between Internet service providers (ISP) and their customers. This unique architecture enables PONs to offer several key benefits, including Reduced operating and management costs.