OPTICAL NETWORK UNIT, OPTICAL SUBSCRIBER LINE TERMINAL DEVICE AND COMMUNICATION CONTROL METHOD

PROBLEM TO BE SOLVED: To provide a communication control method for appropriately determining a communication condition of an ONU (optical network unit) connected to an optical network and controlling reboot of an OLT (optical line terminal). SOLUTION: In communication between the OLT and the ONU, the communication control method controls a time of OLT reboot in accordance with the communication condition of the OLT or the ONU 2 connected to the OLT when the OLT disconnects the communication with the ONU 2 and reboots itself. The ONU 2 has at least one of a queue for temporarily storing data to be sent to the OLT by priority levels and a queue for temporarily storing data received from the OLT by priority levels, and also has a monitoring means for monitoring the presence or absence of data or a data quantity stored in the queues. The ONU 2 avoids reboot of the OLT when the ONU 2 determines that the data of a specific priority level is in the queue. COPYRIGHT: (C)2009,JPO&INPIT