Topology Considerations - Cisco SCE8000 GBE 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:
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?
•
•
Size
A Cisco SCE8000 GBE deployment can range from a single platform to multiple platforms.
A complete discussion on sizing the system is beyond the scope of this document. Information regarding
the number of Cisco SCE8000 GBE 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 SCE8000 GBE functionality? If so, there
must be a backup Cisco SCE8000 GBE platform 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 SCE8000 GBE GBE, the standby Cisco
SCE8000 GBE 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 SCE8000 GBE fail.
Link continuity
How should the Cisco SCE8000 GBE respond to platform failure with regard to link continuity? Should
traffic flow continue even though the unit is not operating, or be halted until the platform is
repaired/replaced?
If link continuity is a high priority, an external optical bypass module can be installed on the link. (See
Link Continuity, page 3-7
In cascade configuration, installation of an external optical bypass module is highly recommended.
Note
Cisco SCE8000 GBE Installation and Configuration Guide
3-2
Monitoring and control — The Cisco SCE8000 GBE monitors and controls traffic flow. Decisions
are enforced by the Cisco SCE8000 GBE depending on the results of the monitoring functions of
the Cisco SCE8000 GBE and the configuration of the .Service Control Application for Broadband
or Mobile solution.
In order to perform control functions, the Cisco SCE8000 GBE must be physically installed as an
inline installation.
Monitoring only — The Cisco SCE8000 GBE monitors traffic flow, but cannot control it.
Either an inline installation or an optical splitter or port SPAN installation may be used for
monitoring only.
and
Chapter 3 Cisco SCE8000 GBE Topology and Topology-Related Parameters
The Cisco SCE8000 GBE Optical Bypass, page 2-10.)
OL-19897-02