Create a Physical Loopback

Action

To create a physical loopback at the port, connect the transmit port to the receive port using a known good fiber cable.

   
NOTE: Make sure you use a single-mode fiber for a single-mode port and multimode fiber for a multimode port. (For OC-192, you must use the appropriate attentuation.)


 

What It Means

When you create and test a physical loopback, you are testing the transmit and receive ports of the PIC. This action is recommended if a field engineer is available to create the physical loop as it provides a more complete test of the PIC.