363-206-295
Transmission and Synchronization Interfaces
Issue 1
December 1997
5-7
Figure 5-3.
OC-3/OC-12 Ring Low-Speed Interfaces (0x1) — Dual Homing
O
L
I
U
O
L
I
U
Main-1
Main-2
Ring
1
Ring
2
Ring
1
Ring
2
FN ( )-1
FN ( )-2
Main B-2
Main B-1
OC-3
OC-3
O
L
I
U
O
L
I
U
Ring
1
Ring
2
Ring
1
Ring
2
FN ( )-1
FN ( )-2
Main B-2
Main B-1
21-Type
OLIUS
22-Type
OLIU
22-Type
OLIU
DS1/DS3/EC-1/OC-3
DDM-2000
OC-12 Shelf
DDM-2000
OC-3 Shelf
TSI
DDM-2000
OC-12 Shelf
TSI
21-Type
OLIU