| 摘要 |
<P>PROBLEM TO BE SOLVED: To restore a high priority service at an early stage when switching from an active device to a backup device. <P>SOLUTION: A controller 12 transfers priority management information of respective active OLTs (optical line terminal) 10a, 10b and 10c to a backup OLT 10d in each update or periodically. When a failure occurs in any of the active OLTs 10a, 10b and 10c, the controller 12 designates an OLT in which the failure occurs and instructs the backup OLT 10d to representatively perform management. When the backup OLT 10d receives update information of management information from the controller 12, the backup OLT 10d stores priority management information transmitted from the controller 12 in a corresponding data area 55a, 55b or 55c of a RAM 54d. When receiving an instruction of representative performance from the controller 12, the backup OLT 10d uses the priority management information of the notified OLT in which the failure occurs to start management of an ONU (optical network unit) being subordinate to the OLT in which the failure occurs. <P>COPYRIGHT: (C)2008,JPO&INPIT |
