Verifying Board-Level Protection Switching

The board-level protection is classified into two modes: Not Extended mode and SCS Extension mode. In the SCS Extension mode, the SCS board is required. This section takes the extended board-level protection by using two OTM stations as an example to describe the test procedure of the board-level protection switching.

Prerequisites

The board-level protection must be configured.

The fiber connections between station A and station B must be complete.

The equipment must be running normally.

Tools, Equipment and Materials

U2000 Web LCT, signal analyzer, optical fiber, flange, optical attenuator

Set-up Diagram

Figure 1 shows the connection for testing the board-level protection switching.

Figure 1 Connection for testing the board-level protection switching

: Fixed optical attenuator

Procedure

Connecting Test Instruments
1. In station A, respectively connect the output and input optical interfaces of the signal analyzer to the input optical interface RO1 and output optical interface TI1 on the client side of the SCS with the fixed optical attenuator in between.
2. In station B, connect the output optical interface TX1 and the input optical interface RX1 on the client side of the TBE with the fixed optical attenuator in between to realize the loopback on the client side, as shown in Figure 1.
3. Test the channel by using a signal analyzer to ensure that no bit error is generated.
Querying the Normal Channel Status of the Station A
1. Log in to the U2000 Web LCT. Double-click NE A in the Main Topology, and the status figure of the NE A is displayed.
2. Right-click a NE icon and select NE Explorer to display the NE Explorer dialog box.
3. Select the NE from the Navigator Tree in the left-hand pane and choose Configuration > Board-Level Protection from the Function Tree.
4. Click Query, a prompt appears to indicate that the operation was successful. Click Close. And all protection groups are listed in the protection group list in the right-hand pane. The switching status of board-level protection should be Idle.
5. Check the board status of board-level protection. If the TBE1 is in slot IU7 and the TBE2 is in slot IU8, then Working Board is 7-TBE; Working Board Status is Usable; Protection Board is 8-TBE; Protection Board Status is Usable, and Active Board is Working Board.
Testing the Protection Switching of the Equipment
1. The switching test of the board-level protection can be performed in two ways.
  - Method 1: fiber removing. In station A, remove the fiber of the RX1 interface of the TBE1, as shown in Figure 1.
  - Method 2: forced switching. In the board-level protection user interface of station A, right-click the desired protection group on the U2000 Web LCT, and select Forced Switching to Protection to perform the switching. Click OK in the dialog box displayed.
2. Check the board status of station A
  - Choose Configuration > Board-Level Protection from the Function Tree. Click Query.
  - In the fiber removing mode, Working Board is 7-TBE; Protection Board is 8-TBE; Switching Status is Auto Switching; and Active Board is Protection Board.
  - In the forced switching mode, Working Board is 7-TBE; Protection Board is 8-TBE; Switching Status is Forced Switching to Protection; and Active Board is Protection Board.
3. Test the services and switching time by using a signal analyzer. The services should be available , no bit error is generated, and the switching time should be less than 50 ms.
4. If all the previous items meet the requirements, two methods can be used to restore the switching status to normal.
  - Reconnect the fiber.
  - Right-click the desired protection group in the Protection Group, and select Clear. Click OK in the dialog box displayed.
5. Click Query, the switching status should be restored to Idle.