| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a technique for enabling smooth provision of a multicast service.SOLUTION: A customer home side device (ONU) 2, on receiving multicast data according to the reception condition of a terminal device 5 from a passive optical network (PON line 3), transfers the multicast data to the terminal device 5. A station side device (OLT) 1a manages the transfer state of the ONU 2 capable of executing the multicast data transfer to the terminal device 5. On the occurrence of a redundancy switchover in the OLT 1a, the ONU 2 allows the transfer state of the ONU 2 to match the reception condition of the terminal device 5.</p> |
