Two Cascaded Sce 2000S For Dual Links - Cisco SCE 2000 4xGBE Installation And Configuration Manual

Physical Topologies

Two Cascaded SCE 2000s For Dual Links

In this topology, two cascaded SCE 2000s are used. This allows a fail-over solution, where in case
of a failure of one SCE 2000, the functionality that the SCE 2000 provides is preserved by the
redundant platform.
Two Cascaded SCE 2000s: Inline Topology
This topology allows both control and monitoring functionality where redundancy is required and
"inline" connection is used. The two SCE 2000s are cascaded, so the primary SCE 2000 process
the traffic of the two links, while the secondary SCE 2000 only bypasses the traffic of its links to
the primary SCE 2000 for processing, and then bypasses the processed traffic back to the link.
The two SCE 2000s also exchange keep-alive messages and subscriber state information.
In case the primary SCE 2000 fails, the two SCE 2000s 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:
Cisco SCE 2000 4xGBE Installation and Configuration Guide
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The two SCE 2000s are simultaneously aware of the subscriber contexts, and subscriber
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states are constantly exchanged between them, such that if the primary SCE 2000 fails, the
secondary can take over with minimum state loss.
Chapter 3 Topology
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