| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To attain quick and efficient path switching by eliminating an excess procedure in the case of switching an active system path to a standby system path. <P>SOLUTION: An optical network is provided with optical cross-connect apparatuses (PXCs) 3, 4 and transmission apparatuses (WDMs) 5 to 8. If a fault occurs in an active system path passing the WDM 5 and the WDM 6, the active system path is switched to the standby system path passing the WDM 7 and the WDM 8. The WDM 5 has a WDM notification protection time in which time required from the sending of an active system path deletion signal up to the sending of an active system path monitoring end signal can be minimized. When a fault of the active system path in the PXC 4 direction occurs, the active system path deletion signal from the PXC 3 is received by the PXC 4 and light in the PXC 3 direction is interrupted. Even when the light interruption is detected, the WDM 5 does not send a state notification signal to the PXC 3 within the notification protection time. Similarly, the WDM 6 also has the WDM notification protection time. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
