Lucent Technologies FT-2000 OC-48 - Page 585

Maintenance Description
Issue 8.0 July 2002
9-33
Figure 9-5. 2-Fiber Ring Protection Switching Architecture (FT-2000
OC-48 Add/Drop-Rings Terminal)
The FT-2000 OC-48 Add/Drop-Rings Terminal must have RElease 3.0.1-ADR or
later software and be equipped with the following circuit packs to support
bidirectional 2-fiber ring protection switching:
■ OC48 Receiver, Add/Drop [OC48 RCVR (A/D)]:TwoOC48RCVR(A/D)
circuit packs are required to interface with OC-48 high-speed lines 1W and
1E. The OC48 RCVR (A/D) circuit pack constantly monitors the incoming
OC-48 signal on the OC-48 high-speed line. If a defect is detected, the
OC48 RCVR circuit pack notifies the OC48 TRMTR (A/D) and LNCTL
circuit packs. The OC48 RCVR (A/D) circuit packs have the following
transmission buses that make 2-fiber ring protection switching possible:
— Abus: This bus allows the local traffic to be dropped.
— Bbus: This bus allows the through traffic from the service STS-3
tributaries of the OC-48 high-speed line to be looped back to the
OC48 TRMTR (A/D) circuit pack and bridged to the protection
STS-3 tributaries when a 2-fiber ring protection switch is required.
(Refer to Table 9-4 for the mapping between the service STS-3
tributaries and the protection STS-3 tributaries.)
OC-48
TRMTR
RCVR
OC-48
1-8
Protection 1
Service 2
OC48
OC48
OC48
OC48
1W 1E
Service 1
Protection 2
9-16
1-8
9-16
OC48
B
Service 1
1-8
Protection 2
9-16
Service 2
1-8
Protection 1
9-16
OC48
A
C
C
A
C
A
A
C
LNCTL
TO SYSCTL/SYSMEM
Control
Transmission
RCVR
TRMTR
B
Low Speed
Interface