Cisco ONS 15600 Reference Manual page 160

8.4 Subnetwork Connection Protection Rings
Figure 8-7
If a fiber break occurs, Node 2 switches its active receiver to the protect signal coming through Node 3
(Figure
Cisco ONS 15600 SDH Reference Manual, Release 9.0
8-8
Basic Four-Node SNCP
ONS 15600 SDH
Node 0
ONS 15454 SDH ONS 15454 SDH
Node 3
ONS 15600 SDH
Node 2
8-8).
Node 1
= Fiber 1 (working)
= Fiber 2 (protected)
Chapter 8 SDH Topologies and Upgrades
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