Abstract: The embodiments of the present invention relate to communications technology, and disclose an optical power measurement method, an Optical Line Terminal (OLT), and an Optical Network Unit (ONU). The method includes: generating a Physical Layer Operation Administration Maintenance (PLOAM) message that includes an identifier of at least one ONU to be measured and information about a time bucket that is allocated to the ONU to be measured and is used for sending upstream optical signals; sending the PLOAM message to the multiple ONUs; receiving the upstream optical signals that are sent, in the allocated time bucket, by the ONU to be measured; and detecting the received upstream optical signals, and determining the optical power of the upstream optical signals. The present invention avoid waste of bandwidth caused in the prior art when the DBA is required to allocate bandwidth to the ONU to be measured for the purpose of detecting the optical power.

Abstract: The present application discloses a method, a system and a related device for transmitting an OMCI message. In the method, an optical line terminal device sends configuration information to an optical network terminal device, where the configuration information is configured to instruct the optical network terminal device to configure a multicast port on the optical network terminal device to an enabled status so as to establish a multicast channel. The optical line terminal device sends an OMCI message that includes multicast information to the optical network terminal device through the multicast channel, where the multicast information includes a multicast port identifier and the multicast port identifier is configured to reflect a mapping between the OMCI message and the multicast port.

Abstract: Embodiments of the present disclosure provide a ranging method for a passive optical network, including: allocating ranging bandwidth to at least two optical network terminals ONTs and providing ranging bandwidth information for the at least two ONTs by using a same downlink frame; opening a quiet window for suspending uplink sending of other ONTs in a ranging process of the at least two ONTs; and receiving ranging responses of the at least two ONTs in the quiet window and calculating ranging results of the at least two ONTs according to the ranging responses of the at least two ONTs. The embodiments of the present disclosure further provide a ranging apparatus for a passive optical network and a passive optical network system.

Abstract: The embodiments of the present invention relate to communications technology, and disclose an optical power measurement method, an Optical Line Terminal (OLT), and an Optical Network Unit (ONU). The method includes: generating a Physical Layer Operation Administration Maintenance (PLOAM) message that includes an identifier of at least one ONU to be measured and information about a time bucket that is allocated to the ONU to be measured and is used for sending upstream optical signals; sending the PLOAM message to the multiple ONUs; receiving the upstream optical signals that are sent, in the allocated time bucket, by the ONU to be measured; and detecting the received upstream optical signals, and determining the optical power of the upstream optical signals. The present invention avoid waste of bandwidth caused in the prior art when the DBA is required to allocate bandwidth to the ONU to be measured for the purpose of detecting the optical power.