Optical Distribution Network
A passive optical distribution network (PON) uses single mode optical fibre in the outside plant, optical splitters and optical distribution frames, duplexed so that both upstream and downstream signals share the same fibre on separate wavelengths. Faster PON standards generally support a higher split ratio of users per PON, but may also use reach extenders/amplifiers where extra coverage is needed. optical splitters creating a point to multipoint topology are also the same technology regardless of the type of PON system, making any PON network upgradable by changing the ONT and OLT terminals at each end, with minimal change to the physical network.
Access networks usually also must support point-to-point technologies such as Ethernet, which bypasses any outside plant splitter to achieve a dedicated link to the Central Office. Some PON networks use a "home run" topology where roadside cabinets only contain patch panels so that all splitters are located centrally. While a 20% higher capital cost could be expected, home run networks may encourage a more competitive wholesale market since providers' equipment can achieve higher utilisation.
Read more about this topic: Network Access
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