11-12
Cisco ONS 15454 SDH Reference Manual, R5.0
April 2008
Chapter11 SDH Topologies and Upgrades
11.2.5 MS-SPRing Fiber Con nections
11.2.5 MS-SPRing Fiber Connections
Plan your fiber connections and use the same plan for all MS-SPRing no des. For example, make the east
port the farthest slot to the right and the west port the farthest slot to the left. Plug fiber connected to an
east port at one node into the west port on an adjacent node . Figure 11-11 shows fiber connections for a
two-fiber MS-SPRing with trunk cards in Slot 5 (west) and Slot 12 (east). Refer to the
CiscoONS 15454 SDH Procedure Guide for fiber connection procedures.
Note Always plug the transmit (Tx) connector of an STM-N car d at one node into the receive (Rx)
connector of an STM-N card at the adjacent node. Cards display an SF LED when Tx and Rx
connections are mismatched.
Figure11-11 Connecting Fiber to a Four-Node, Two-Fiber MS-SPRing
For four-fiber MS-SPRings, use the same east-west connection pattern for the working and protect
fibers. Do not mix working and protect card connections. The MS-SPRing does not function if working
and protect cards are interconnected. Figure11-12 shows fiber connections for a four-fiber MS-SPRing.
Slot 5 (west) and Slot 12 (east) carry the working traffic. Slot 6 (west) and Slot 1 3 (east) carry the protect
traffic.
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Node 1
West East
West East
West East
West East
Slot 5
Tx
Rx
Slot 12
Tx
Rx
Node 4
Slot 5
Tx
Rx
Slot 12
Tx
Rx
Node 2
Slot 5
Tx
Rx
Slot 12
Tx
Rx
Node 3
Slot 5
Tx
Rx
Slot 12
Tx
Rx