Chapter 5
SONET Topologies
Figure 5-20 A basic four-node UPSR
Figure 5-21 A UPSR with a fiber break
Span 4
Span 3
November 2001
ONS 15454
Node ID 0
ONS 15454
Node ID 3
ONS 15454
Node ID 2
Source
ONS 15454
Node ID 0
Span 5
ONS 15454
Node ID 3
Span 6
Destination
ONS 15454
Node ID 2
ONS 15454
Node ID 1
= Fiber 1
= Fiber 2
Span 1
Span 8
ONS 15454
Node ID 1
Span 7
Span 2
Fiber
break
= Fiber 1
= Fiber 2
Cisco ONS 15454 Installation and Operations Guide
Unidirectional Path Switched Rings
5-27