A passive optical network is a kind of fiber-optic network in form of a point-to-multipoint topology, utilizing optical splitters to deliver data from a single transmission point to multiple user endpoints. In practice, PONs are typically used for the last mile between Internet service providers (ISP) and their customers. In this use, a PON. A complete and systematic overview of passive optical access networks is presented in this paper, concerning both the hot research topics and the main operative issues about the design guidelines and the deployment of Passive Optical Networks (PON) architectures, nowadays the most commonly. We are working on new solutions for upcoming generations of passive optical networks. Recently, we have developed and characterized a real-time OFDM-PON prototype for data rates of 100 Gbit/s and beyond. This PON architecture is increasingly becoming.