Time- and wavelength-division multiplexed passive optical network (TWDM-PON) is a primary solution for the next-generation passive optical network stage 2 (NG-PON2) by the full service access network (FSAN) in April 2012.OverviewA passive optical network (PON) is a telecommunications network that uses only unpowered devices to carry signals, as opposed to electronic equipment. In practice, PONs are typically used for the. A passive optical network consists of an (OLT) at the service provider's central office (hub), passive (non-power-consuming) optical splitters, and a number of (ONUs) or Passive optical networks were first proposed by in 1987. Two major standard groups, the (IEEE) and the.