Cisco Systems 15454 SDH 11.2.2 Four-Fiber MS-SPRings

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Cisco ONS 15454 SDH Reference Manual, R5.0
April 2008
Chapter11 SDH Topologies and Upgrades
11.2.2 Four-Fiber MS-SPRings
11.2.2 Four-Fiber MS-SPRings
Four-fiber MS-SPRings double the bandwidth of two-fiber MS-SPRings. Because they allow span
switching as well as ring switching, four-fiber MS-SPRings increase the reliability and flexibility of
traffic protection. Two fibers are allocated for working traffic and two fibers for protection, as shown in
Figure 11-4. To implement a four-fiber MS-SPRing, you must install four STM-16 cards or four STM-64
cards at each MS-SPRing node.
Figure11-4 Four-Node, Four-Fiber MS-SPRing
Node 0
Node 1
Node 2
Node 3
Span 1
Span 2Span 3
Span 4
Span 8
Span 7Span 6
Span 5
STM-16 Ring
= Working fibers
= Protect fibers
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