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Cisco ONS 15454 Reference Manual, R7.0
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Chapter 12 SONET Topologies and Upgrades
12.2 12.2.5 BLSR Fiber Connections
12.2.5 BLSR Fiber Connections
Plan your fiber connections and use the same plan for all BLSR nodes. 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 12-11 shows fiber connections for a
two-fiber BLSR with trunk cards in Slot 5 (west) and Slot 12 (east). Refer to the Cisco ONS 15454
Procedure Guide for fiber connection procedures.
Note Always plug the transmit (Tx) connector of an OC-N card at one node into the receive (Rx)
connector of an OC-N card at the adjacent node. Cards display an SF LED when Tx and Rx
connections are mismatched.
Figure 12-11 Connecting Fiber to a Four-Node, Two-Fiber BLSR
For four-fiber BLSRs, use the same east-west connection pattern for the working and protect fibers. Do
not mix working and protect card connections. The BLSR does not function if working and protect cards
are interconnected. Figure 12-12 shows fiber connections for a four-fiber BLSR. Slot 5 (west) and
Slot 12 (east) carry the working traffic. Slot 6 (west) and Slot 13 (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