Nortel ICS Install Manual page 568

568 / Tests
Payload loopback
Norstar ICS
Norstar ICS
The payload loopback test loops the received information bits
(192 per frame) back to the network. The payload loopback
test can also be invoked and stopped remotely via the facility
data link (FDL) in extended super frame (ESF) format.
The payload loopback test must be run in coordination with the
T1 service provider. Some test patterns can cause the DTI to
reset. To avoid this, start the payload loopback test from your
system before the T1 service provider begins their test, and
stop the payload loopback test from your system after the T1
service provider ends their test.
Modular ICS 7.1 Installer Guide
T1
T1
network
network
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