![](/images/new-backgrounds/1299589/299589109x1.webp)
Example: Network with Three Concentrators and a Fourth Concentrator in Full Redundancy Configuration
In the following example, three concentrators are active.
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| Concentrator A |
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| 500 m |
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| Concentrator B |
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| 1 km |
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| 500 m |
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| 1 km |
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| 500 m |
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| Primary Link | ||||||||||||||||||
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| Backup Link | |||||||||||||||
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| C |
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| D | Normal Link | |||||||||||||||||||||
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500 m
500 m
Fiber cable
Transceivers |
Figure 2-12. Network With 3 Concentrators
Concentrator B is a redundant concentrator for Concentrator A. The fiber equivalent distance between transceivers attached to Concentrators C and D is:
3 * 560 m + 500 m + 1000 m + 500 m + 500 m = 4180 meters
Because the sum is less than 4200 meters, the configuration is legal.