This section describes the application of IPA.
As shown in
Figure 1, an IPA pair is configured between stations A and B. When a fiber break occurs on the link between stations A and B, the IPA starts and the optical amplifier in the upstream of the fiber break
point is shut down to ensure the maintenance personnel's safety. When the optical signals of the system are restored, the IPA stops and the optical amplifier normally operates again.
Figure 1 Diagram of IPA application