12-16
Cisco ONS 15454 Reference Manual, R8.5.x
78-18106-01
Chapter 12 SONET Topologies and Upgrades
12.3 Path Protection
Figure 12-14 Path Protection with a Fiber Break
Figure 12-15 shows a common path protection application. OC-3 optics provide remote switch
connectivity to a host Telcordia TR-303 switch. In the example, each remote switch requires eight DS-1s
to return to the host switch. Figure 12-16 on page 12-18 and Figure 12-17 on page 12-18 show the shelf
layout for each site.
Span 1
Span 2
Span 3
Span 4
Span 8
Span 7Span 6
Span 5
Fiber
break
Source
Destination
32639
ONS 15454
Node ID 0
ONS 15454
Node ID 1
ONS 15454
Node ID 2
ONS 15454
Node ID 3
= Fiber 1
= Fiber 2