Abstract: A manner of managing data transmission and operating-mode transitions in a communication network. A network node having a transmitter and receiver is selectively transitioned into a Transmit state, where the Transmit state is a condition wherein the transmitter is turned on for data transmission only during timeslots provided for by a PBW (pre-allocation bandwidth) and remains off otherwise. The PBW and clock drift allowance permits the receiver to remain off during all or most of the Transmit state.

Abstract: An optical network element is configured to operate in a primary operational state in which the optical network element can exchange optical signals with at least one further optical network element, particularly an optical line terminal of a passive optical network PON. The optical network element is configured to operate in at least one secondary operational state in which an electrical power consumption of the optical network element is lower as compared to the primary operational state. The optical network element is configured to directly transit from the primary operational state to the at least one secondary operational state.