Optical network unit, central office node and methods of configuring an optical network unit

Abstract

An optical network unit, ONU, for a passive optical network, PON. The ONU comprises a tunable receiver having a wavelength tunable operating wavelength, a tunable transmitter having a wavelength tunable operating wavelength and a controller comprising at least one processor and memory. The memory contains instructions which when executed by the at least one processor cause the ONU to perform operations of: if the tunable transmitter is on, switching the tunable transmitter off and if the tunable receiver is off, switching the tunable receiver on; determining an availability of a control channel; receiving a downstream control channel signal at a downstream control channel wavelength from a central office, CO, node of the PON, the downstream control channel signal carrying an indication of allocated operating wavelengths for the ONU; setting an operating wavelength of the tunable receiver to an allocated operating wavelength and setting the operating wavelength of the tunable transmitter to an allocated operating wavelength; and switching the tunable transmitter on.