Create The Terminal (Inward) Loopback On A Destination Ds-N Port - Cisco ONS 15454 Troubleshooting Manual

Chapter 1 General Troubleshooting
Completing a successful terminal loopback to a destination node DS-N port verifies that the circuit is
good to the destination DS-N.
DS-N port.
Figure 1-13 Terminal (Inward) Loopback on a Destination DS-N Port
Test Set
Caution Performing a loopback on an in-service circuit is service-affecting. To protect traffic, apply a lockout or
force switch to the target loopback port. For more information about these operations, refer to the
Cisco ONS 15454 Procedure Guide.
DS-3 terminal loopbacks do not transmit an AIS condition in the direction away from the loopback.
Note
Instead of a DS-3 AIS, a continuance of the signal transmitted to the loopback is provided.

Create the Terminal (Inward) Loopback on a Destination DS-N Port

Step 1 Connect an electrical test set to the port you are testing:
a.
b.
c.
In CTC node view, click the Circuits tab and click Create.
Step 2
In the Circuit Creation dialog box, choose the type and size, such as an STS-1.
Step 3
Click Next.
Step 4
Step 5 In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as
"DS-NtoDS-N."
Leave the Bidirectional check box checked.
Step 6
Step 7 Click Next.
Step 8 In the Circuit Creation source dialog box, select the Node, card Slot, Port, and STS (or VT) where the
test set is connected.
Step 9 Click Next.
Step 10 In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used
for the source dialog box.
November 2004
Source
ONS Node
DS-N
If you just completed the "Perform a Hairpin Test on a Source Node Port (West to East)" procedure
on page 1-12, leave the electrical test set hooked up to the DS-N port in the source node.
If you are starting the current procedure without the electrical test set hooked up to the DS-N port,
use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the DSx panel
or the EIA connectors for the port you are testing. Both Tx and Rx connect to the same port.
Adjust the test set accordingly.
1.3.4 Perform a Terminal (Inward) Loopback on a Destination DS-N Port (West to East)
Figure 1-13 shows an example of a terminal loopback on a destination
XC OC-N
Cisco ONS 15454 Troubleshooting Guide, R4.6
Destination
ONS Node
OC-N XC DS-N
1-19