363-206-285
Maintenance Description
Issue 3 June 2001
9-19
Figure 9-8. Maintenance Signaling — VT Ring Application, Unequipped
Ring 2
DS1
DS1 AIS*
VT-Path Yellow*
Ring 1
Ring 2
Ring 1
M
A
I
N
1
M
A
I
N
2
M
A
I
N
1
M
A
I
N
2
STS-Path Yellow
Ring 1
VT-Path AIS
STS-Path Yellow
M
A
I
N
1
M
A
I
N
2
M
A
I
N
1
M
A
I
N
2
VT-Path AIS*
DDM-2000
OC-3
STS Unequipped
VT-Path Yellow*
DS1
VT-Path Yellow*
OC-N
EC-1
STS Unequipped
DDM-2000
OC-3
DDM-2000
OC-3
VT Unequipped
VT Unequipped
DDM-2000
OC-3
VT Unequipped VT Unequipped
VT Unequipped*
OC-N
EC-1
* These signals are sent only when the failed VT
path is selected.
These signals are sent on pass through or continue paths.
â€
â€
â€
â€
OC-N‡
OC-N‡
OC-N‡ OC-N‡
OC-N‡ OC-N‡ OC-N‡ OC-N‡
‡
N is 1 or 3
VT AISâ€
DS1 AIS*
§
§
§
VT AIS with 22D-V, 22G-U and 22G2-U OLIUs.