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Cisco SCE 2000 4xGBE Installation and Configuration Guide
OL-7824-06
Chapter 3 Information About Topology
Information About Topology Considerations
In case the primary SCE 2000 fails, the two SCE 2000 s switch their roles, and this way fail-over is
provided.
Figure 3-5 Two SCE Platforms: Dual Link Inline Topology
This fail-over solution preserves the SCE 2000 functionality and the network link:
• The two SCE 2000 s are simultaneously aware of the subscriber contexts, and subscriber states are
constantly exchanged between them, such that if the primary SCE 2000 fails, the secondary can
take over with minimum state loss.
• When one SCE 2000 fails (depending on the type of failure) its link traffic is still bypassed to the
functioning SCE 2000 and processed there, so the traffic processing continues for both the links.
• The bypass of the traffic through the failed SCE 2000 is configurable, and the user may choose to
always cutoff the line that goes through the failed SCE 2000 . In this case network redundancy
protocols like HSRP are responsible for identifying the line cutoff and switching all the traffic to go
through the functioning SCE 2000 .
LINK
RX
Cisco SCE 2000 Series
4xGBE
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MM TX
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LINE/CASCADE NET
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Cisco SCE 2000 Series
4xGBE
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MM TX
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GBE-1
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PWR B
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PWR A
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GBE-2
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Router
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RouterRouter
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