This disclosure relates to wavelength division multiplexed (WDM) passive optical networks (PON), and the transmission of point-to-point and broadcast or multicast channels from an optical line transmitter (OLT) to an optical network unit (ONU). There is provided a WDM PON (100) comprising: an OLT (105) coupled to a plurality of ONU (110a, 110b) using an optical fiber network (160); the OLT (105) having one or more WDM transceivers (115a, 115b) each arranged to receive multi-cast and point-to-point channels and wherein the or each WDM transceiver (115a, 115b) is arranged to transmit a said channel to a respective said ONU (110a, 110b) using a respective dedicated wavelength (λa, λb); an input channel switch (130a, 130b) associated with the or each WDM transceiver (115a, 115b) and arranged to selectively couple the input of the WDM transceiver to the multi-cast channels and the point-to-point channels (140,135); wherein the selected multi-cast or point-to-point channels are directly converted to the respective dedicated wavelength.