363-206-305
Administration and Provisioning
Issue 3 June 2000
8-43
Path protection switching is employed for dual-homed applications, just like in
single-homed applications. That is, path switching is supplied by the remote DDM-
2000 FiberReach nodes and the DDM-2000 OC-3 systems in the wire center.
However, the OC-3 host node configuration is different than single homing. Since
an OC-3 host node terminates only one leg of the OC-1 extension, it employs a
0x1 low-speed interface to the OC-1 ring extension. The dual OC-1 circuit pack
can be unprotected in a dual-homed application. Dual- and single-homed
extensions can also be mixed at a host node, allowing the access network to be
tailored efficiently to different groups of customers.
Example Cross-Connections
8
The cross-connect commands at each node in Figure 8-3 are as follows:
â–
At RT1 and RT2:
ent-crs-vt1:m-1-2-3,m-1-2-3:cct=twoway;
The VT signal in the ring is only passing through these sites, so two-way
cross-connections with identical addresses are provisioned here.
â–
At RT3 and RT4:
ent-crs-vt1:m-1-2-3,b-1-4-7:cct=twoway;
At these sites, the VT1.5 signal is routed between a timeslot on the OC-3
ring and a timeslot on the OC-1 ring.
â–
At FiberReach:
ent-crs-vt1:m-1-4-7,c-1-4:cct=twoway;
At this site, the signal is routed from a DS1 interface to the same timeslot
on both rotations of the OC-1 ring. In the other direction, the VT1.5 signals
received from both rotations of the OC-1 ring are monitored, path
protection switching is provided, and the selected signal is routed to the
DS1 interface.
â–
At CO:
ent-crs-vt1:m-1-2-3,b-1-1:cct=twoway;
At this site, the signal is routed from a DS1 interface to the same timeslot
on both rotations of the OC-3 ring. In the other direction, the VT1.5 signals
received from both rotations of the OC-3 ring are monitored, path
protection switching is provided, and the selected signal is routed to the
DS1 interface.