Application of Client 1+1 Protection

As shown in Figure 1 station A and station B form a point-to-point network in project T. Both A and B are OTM stations. The client 1+1 protection is adopted between the two stations. Each station is configured with one SCS board and two OTUs that have the convergence function.

See Figure 1.

When signals are transmitted from station A to station B, the SCS board in station A sends signals to the working OTU (OTU1) and the protection OTU (OTU2) at the same time. When signals reach the OTU1 and OTU2 in station B, only the signals sent from the OTU1 are transmitted to the client-side equipment through the SCS board.

Figure 1 Application of client 1+1 protection (normal)

: Direction of the working signal flow

: Direction of the protection signal flow

When signals are transmitted from station B to station A, the SCS board in station B sends signals to the OTU1 and the OTU2 at the same time. In station A, only the signals sent from the OTU1 are transmitted to the client-side equipment through the SCS board.

Figure 2 Application of client 1+1 protection (switching)

: Direction of the working signal flow

: Direction of the protection signal flow

See Figure 2.

In the direction from station A to station B:

In station A, the fiber (used to transmit client service a) between the SCS board and the input port of the OTU1 breaks. After detection and control, only the OTU2 in station B sends the client-side signals to the client-side equipment through the SCS board. Client service b is still transmitted by the original route.

In the direction from station B to station A:

There is no switching because the working wavelength route is normal, and the route of signals remains the same.