Topology Considerations - Cisco SCE 8000 Installation And Configuration Manual

Topology Considerations

Topology Considerations
There are several issues that must be considered in order to arrive at the optimum configuration of the
topology-related parameters:
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Note In cascade configuration, installation of an external optical bypass module is required.
Cisco SCE8000 GBE Installation and Configuration Guide
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Functionality
Will the system be used solely to monitor traffic flow, with report functionality only, or will it be
used for traffic flow control, with enforcement as well as report functionality?
Monitoring and Control—The Cisco SCE 8000 monitors and controls traffic flow. Decisions are
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enforced by the Cisco SCE 8000 depending on the results of the monitoring functions of the
Cisco SCE 8000 and the configuration of the Service Control Application for Broadband or
Mobile solution.
To perform control functions, the Cisco SCE 8000 must be physically installed as an inline
installation.
Monitoring only—The Cisco SCE 8000 monitors traffic flow, but cannot control it.
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Either an inline installation or an optical splitter or port SPAN installation may be used for
monitoring only.
Size
The Cisco SCE 8000 deployment can range from a single 10 GBE link to multiple platforms in a
MGSCP topology.
A complete discussion on sizing the system is beyond the scope of this document. Information about
the number of Cisco SCE 8000 platforms required is related to the design considerations 'per link'
(topology and redundancy factors) rather than to overall sizing of the system.
Redundancy
Must the system be designed to guarantee uninterrupted Cisco SCE 8000 functionality? If so, there
must be a backup Cisco SCE 8000 platform (or a backup for each platform in an MGSCP topology)
to assume operation in case of failure of the primary device.
A backup SCE platform is connected in a cascade configuration with the primary SCE platform so
that, although all processing is performed only in the active Cisco SCE 8000, the standby Cisco SCE
8000 is constantly updated with all the necessary information so that it can instantly take over
processing the traffic on the data links should the active Cisco SCE 8000 fail.
A MGSCP topology with multiple Cisco SCE 8000 platforms provides more sophisticated
redundancy options, but the basic decision on each link is the same: does it require a standby SCE
platform or not?
Link continuity
How should the Cisco SCE 8000 respond to platform failure in relation to link continuity? Should
traffic flow continue even though the unit is not operating, or should it be halted until the platform
is repaired or replaced?
If link continuity is a high priority, an external optical bypass module can be installed on the link.
(See "Link Continuity" section on page 3-11
page 2-12.)
Chapter 3 Cisco SCE 8000 Topology and Topology-Related Parameters
and "The Cisco SCE 8000 Optical Bypass" section on