An Optical Network Unit, ONU, for using in an Ethernet Passive Optical Network, EPON,, comprising: a memory configured to store logic instructions; and processor circuitry configured, by executing the logic instructions, to: receive a GATE message from an Optical Line Terminal, OLT, (102, 702); and determine whether the GATE message includes a broadcast Logical Link Identifier, LLID, or a multicast LLID; characterized in that the processor circuitry is further configured to: if the GATE message includes the broadcast LLID or the multicast LLID, transmit a REPORT message to the OLT (102, 702), in response to the GATE message, when data is available for upstream transmission at the ONU (104, 704, 706) and when a probabilistic reporting, PR, mode is enabled, the PR mode defining that a periodic polling is suspended for the ONU (104, 704, 706), and not to transmit any REPORT messages (510,518), if the PR mode is disabled or when no data is available for upstream transmission at the ONU (104,704,706). a memory configured to store logic instructions; and processor circuitry configured, by executing the logic instructions, to: receive a GATE message from an Optical Line Terminal, OLT, (102, 702); and determine whether the GATE message includes a broadcast Logical Link Identifier, LLID, or a multicast LLID; characterized in that the processor circuitry is further configured to: if the GATE message includes the broadcast LLID or the multicast LLID, transmit a REPORT message to the OLT (102, 702), in response to the GATE message, when data is available for upstream transmission at the ONU (104, 704, 706) and when a probabilistic reporting, PR, mode is enabled, the PR mode defining that a periodic polling is suspended for the ONU (104, 704, 706), and not to transmit any REPORT messages (510,518), if the PR mode is disabled or when no data is available for upstream transmission at the ONU (104,704,706). receive a GATE message from an Optical Line Terminal, OLT, (102, 702); and determine whether the GATE message includes a broadcast Logical Link Identifier, LLID, or a multicast LLID; characterized in that the processor circuitry is further configured to: if the GATE message includes the broadcast LLID or the multicast LLID, transmit a REPORT message to the OLT (102, 702), in response to the GATE message, when data is available for upstream transmission at the ONU (104, 704, 706) and when a probabilistic reporting, PR, mode is enabled, the PR mode defining that a periodic polling is suspended for the ONU (104, 704, 706), and not to transmit any REPORT messages (510,518), if the PR mode is disabled or when no data is available for upstream transmission at the ONU (104,704,706). if the GATE message includes the broadcast LLID or the multicast LLID, transmit a REPORT message to the OLT (102, 702), in response to the GATE message, when data is available for upstream transmission at the ONU (104, 704, 706) and when a probabilistic reporting, PR, mode is enabled, the PR mode defining that a periodic polling is suspended for the ONU (104, 704, 706), and not to transmit any REPORT messages (510,518), if the PR mode is disabled or when no data is available for upstream transmission at the ONU (104,704,706).