Cisco Cisco ONS 15454 SONET Multiservice Provisioning Platform (MSPP) Guía De Diseño
OL-4556-01
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Figure 2-35: Three Node Linear ADM Network
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Slot 6 to Slot 6
Slot 5 to Slot 5
Slot 12 to Slot 12
Slot 13 to Slot 13
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When used in a Linear ADM configuration, each ONS 15454 has direct access to Westbound or
Eastbound STS channels at intermediate sites along the fiber route. Cisco ONS 15454 ADM
configurations eliminate the need for costly “back-to-back” terminal nodes, and can be enhanced
with protection spans for any OC-N rate. Figure 2-36 shows the traffic flow for a typical linear
ADM network. Each ONS 15454 node requires two fibers, working and protect optical
transmitters and receivers in both directions, and local drops for insertion and termination of any
signal in the route.
Figure 2-36: Linear ADM Traffic Flow
OC-48
Working
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OC-48
Protect
OC-48
Protect
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B A
STS-N Path
ONS
15454
ONS
15454
ONS
15454
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A B C
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STS-N Path
ONS
15454
ONS
15454
ONS
15454
2-Fiber Bi-directional Path Switched Ring
A Bi-directional Line Switched Ring (BLSR) is a self-healing ring configuration used to connect
two or more adjacent ONS 15454 nodes. The protected network design of a BLSR helps it
survive cable cuts and node failures by providing redundant, geographically diverse paths for
each SONET span.