Verifying VLAN SNCP Switching

This section takes a ring network formed by two stations which the L4G board is used as an example to describe the test procedure of the VLAN SNCP protection switching. Only the 11LEX4, 11LEM24, L4G and TBE boards support the VLAN SNCP protection.

Prerequisites

The VLAN SNCP 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

The diagram of testing VLAN SNCP protection switching is shown in Figure 1.

Figure 1 Testing VLAN SNCP protection switching

: Fixed optical attenuator

1,2.3,4: L4G Board

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 RX and output optical interface TX on the client side of the OTU with the fixed optical attenuator in between.
2. In station B, connect the input optical interface RX and the output optical interface TX on the client side of the OTU 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 Station A
1. Log in to the U2000 Web LCT. Double-click the 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 desired Ethernet board in the NE Explorer, and choose Configuration > Ethernet Service > Ethernet Line Service from the Function Tree.
4. Click the VLAN SNCP Service Management tab. Select one service. Click Query, all the current protection groups are displayed. Current Status of VLAN SNCP should be Normal State.
5. Query the channel states of the VLAN SNCP protection. Link Status of the working service is Normal, and Link Status of the protection service also is Normal.
Testing the Protection Switching of the Equipment
1. The switching test of the VLAN SNCP protection can be performed in two ways.
  - Method 1: fiber removing. Remove the fiber in the IN optical interface of the working OTU 2 in station A to perform the switching, as shown in Figure 1.
  - Method 2: forced switching. On the U2000 Web LCT, log on into station A. In the VLAN SNCP Service Management, choose working service, click Set Switching. Select Force to Protection in the displayed menu to perform the switching. Click OK in the dialog box displayed.
2. Query the channel states of the VLAN SNCP protection in station A.
  - Choose Configuration > Ethernet Service > Ethernet Line Service from the Function Tree. Click the VLAN SNCP Service Management tab. Select one service. Click Query, all the current protection groups are displayed.
  - In the fiber removing mode, Link Status of the working service is SF, Link Status of protection service is Normal, Current Status of the protection group is SF Switching.
  - In the forced switching mode, Link Status of the working service is Normal, Link Status of the protection service is Normal, Current Status of the protection group is Forced (from Working to Protection) Switching State.
3. In the NE panel of the Station A, right-click the L4G board and select Browse Current Alarms.
  - If the protection group is automatically switched, the L4G board reports AUTOSW-VLAN.
  - If the protection group is forced switched, the L4G board reports FRCDSW-VLAN.
4. Test the services by using a signal analyzer. The services should be available, and no bit error is generated.
5. To restore the test environment of the two switching modes in Step 1, the following two modes can be respectively used:
  - Fiber removing mode: Reconnect the fiber.
  - Forced switching mode: Select the working service, and click Set Switching. In the displayed menu, select Clear. Click OK in the dialog box displayed.
  NOTE:
  If the Restore Mode field is set to Non-Revertive, select the desired working cross-connection, and click Set Switching. In the displayed menu, choose Manual to Working. After that, right-click the same working cross-connection again, click Set Switching. In the displayed menu, choose Clear. Click OK in the dialog box displayed.
6. Click Query. A prompt appears to indicate that the operation was successful. Click Close. Current Status of the protection group should be Normal State.