Cisco 15454-DS1-14= - 1.544Mbps Expansion Module Reference Manual page 432

12.4.2 Path Protection DRI
Figure 12-22
Figure 12-23
traffic routing occurs at two nodes, rather than four. This is achieved by installing an additional OC-N
trunk at the two interconnect nodes.
Cisco ONS 15454 Reference Manual, R8.5
12-24
ONS 15454 Traditional Path Protection Dual-Ring Interconnect
Node 3
Node 4
Node 6
Bridge
Path Selector
Primary Path, Primary
Primary Path, Secondary
Return Path, Primary
Return Path, Secondary
shows ONS 15454 nodes in an integrated DRI topology. The same drop-and-continue
Node 1
UPSR
Ring 1
Node 5
Duplicate
Signals
Node 7
UPSR
Ring 2
Chapter 12 SONET Topologies and Upgrades
Node 2
Pass-through
Node
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