Maintenance Description
9-72 Issue 8.0 July 2002
Loopbacks 9
Low Speed (DS3, EC-1, OC-3, and OC-12) 9
The FT-2000 OC-48 Lightwave System allows the following loopbacks to be
performed:
■ A low-speed DS3 loopback allows a single DS3 signal or all the DS3
signals to be looped back toward the OC-48 high-speed line. The DS3
loopback only allows a single DS3 signal to be looped back toward the
OC-48 high-speed line. The input DS3 signal(s) from the DSX-3
cross-connect panel are preempted by this loopback, but the output DS3
signal(s) to the DSX-3 cross-connect panel remain connected.
■ A low-speed EC-1 loopback allows an EC-1 signal or all the EC-1 signals
to be looped back toward the OC-48 high-speed line. In Release 6.0.1, the
EC-1 loopback only allows a single EC-1 signal to be looped back toward
the OC-48 high-speed line. The input EC-1 signal(s) from the STSX-1
cross-connect panel are preempted by this loopback, but the output EC-1
signal(s) to the STSX-1 cross-connect panel remain connected.
■ Low-speed OC-3 loopbacks allow a single OC-3 signal to be looped back
toward the OC-48 high-speed line or toward the OC-3 line. A loopback may
be active in only one direction at a time. Simultaneous loopbacks in both
directions are not supported. When a loopback is established toward the
OC-48 high-speed line, the input OC-3 signal from the OC-3 line is
preempted, but the output OC-3 signal transmitted toward the OC-3 line
remains connected. When a loopback is established toward the OC-3 line,
the OC-3 signal from the OC-48 high-speed line is preempted, but the
OC-3 signal transmitted toward the OC-48 high-speed line remains
connected.
■ Low-speed OC-12 loopbacks allow a single OC-12 signal to be looped
back toward the OC-48 high-speed line or toward the OC-12 line. A
loopback may be active in only one direction at a time. Simultaneous
loopbacks in both directions are not supported. When a loopback is
established toward the OC-48 high-speed line, the input OC-12 signal from
the OC-12 line is preempted, but the output OC-12 signal transmitted
toward the OC-12 line remains connected. When a loopback is established
toward the OC-12 line, the OC-12 signal from the OC-48 high-speed line is
preempted, but the OC-12 signal transmitted toward the OC-48 high-speed
line remains connected.
These loopbacks are made electronically within the DS3, STS1E, OC3 (1.3 STD),
and OC12 (1.3 STD) circuit packs in response to the
FAULT-Operate-Loopback-T3, FAULT-Operate-Loopback-EC1,
FAULT-Operate-Loopback-OC3 and FAULT-Operate-Loopback-OC12
inputs entered at the CIT. The FAULT-Release-Loopback-T3,
FAULT-Release-Loopback-EC1, FAULT-Release-Loopback-OC3,
FAULT-Release-Loopback-OC12 inputs are used to take down loopbacks.
To Next Page
Loading...