363-206-295
Maintenance Description
Issue 1 December 1997 9-13
Figure 9-4. Maintenance Signaling — Path Switched Ring Applications (Sheet 2 of 4)
DDM-2000
Ring 2
Ring 1
LOS
LOF
Line AIS
DDM-2000
Ring 2
Ring 1
STS path AIS
DDM-2000
Ring 2
Ring 1
FERF
M
A
I
N
B2
M
A
I
N
M
A
I
N
STS-Path Yellow
STS-Path Yellow‡
FERF
M
A
N
B1
I
OC-12
B1
B2
M
A
I
N
B2
M
A
I
N
B1
OC-12
OC-12 OC-12
OC-12
OC-12
â€
‡
STS-path AISâ€
STS-Path AIS*
STS-Path Yellow‡
STS-LOP
STS-path AISâ€
* Signal is sent on STS-1 paths selected from the failed ring (ring 1)
Signal is sent on pass-through and continue paths only
STS path yellow is passed to the EC-1 or OC-12 interface depending
on whether the STS-1 path is a drop or pass-through connection
EC-1 or
OC-3/OC-3c
STS-Path AIS*
EC-1 or
OC-3/OC-3c
EC-1 or
OC-3/OC-3c