363-206-305
Maintenance Description
Issue 3 June 2000
9-19
Dual-Homed Ring Interworking Application
9
Figure 9-8 shows a dual-homed FiberReach configuration. This application
requires two DDM-2000 OC-3 Multiplexers to provide redundant points of
interconnection between the FiberReach and the DDM-2000 OC-3 ring. The
same 0x1 interface is used as for the single-homed application. However, for the
dual-homing application, only one 27-type OLIU is required in the DDM-2000
OC-3 function unit to interface one side of the FiberReach ring.
Another FiberReach extension can use the remaining -1 or -2 slots, as long as the
bandwidth is not violated. For instance, assume you had a dual homed
application where one OC-3 shelf is hosting and terminating one rotation of the
subtending OC-1 ring through OC-1 port # 1 on the dual OC-1 (27-type OLIU) in
FN-A-1, and another OC-3 shelf is hosting and terminating the other rotation of
the subtending OC-1 ring through the OC-1 port #1 on the dual OC-1 (27-type).
As a result, both 27-type OLIU circuit packs located in FN-A-1 of one OC-3 shelf
and FN-A-2 of the other OC-3 shelf still have one OC-1 port available (OC-1 #2) to
be used for another dual-homed application to host another OC-1 ring, or this
OC-1 port can be used to host a single-homed application, which in this case
requires the presence of another 27-type OLIU in FN-A-2.