Setting a Loopback for an SDH Interface (RTN NEs)

You can set a loopback for an SDH interface by using the U2000 Web LCT. The SDH interface loopback is a common fault location method used to test and maintain the SDH board. The SDH interface loopback is used to test the fiber connections and interfaces on the SDH board, and is also used to test the SDH service processing module and the cross-connect board.

Context

The SDH interface loopback can be set to an outloop or an inloop.

When an outloop is used, the SDH signal received by the NE is returned at the SDH interface. See Figure 1. An outloop is used to test the fibers connections and interfaces on the SDH board.
Figure 1 Outloop
When an inloop is used, the SDH signal transmitted by the NE is returned to the cross-connect board at the SDH interface. See Figure 2. An inloop is used to test the SDH service processing module and the cross-connect board.
Figure 2 Inloop

NOTICE:

As a loopback interrupts services, it is only used for fault location and must be released after the fault is removed.

Procedure

In the NE Explorer, select a board and choose Configuration > SDH Interface from the Function Tree.
Select By function and select Optical (Electrical) Interface Loopback.
Select an SDH interface from the list and double-click Optical (Electrical) Interface Loopback to choose a loopback mode.
Click Apply and the Confirm dialog box is displayed.
Click OK and the Prompt dialog box is displayed.
Click OK. A prompt is displayed indicating that the operation is successful.
Click Close.