The ONU management module is configured to receive a message from the ONU that {HEAD ~ the ONU} has switched to an active mode from {TAIL ~ the sleep mode} to receive the received data traffic from the OLT over the optical line 
The ONU management module is configured to receive a message from the ONU that { HEAD ~ the ONU } has switched to an active mode from { TAIL ~ the sleep mode } to receive the received data traffic from the OLT over the optical line
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH