Technology Refresh upgrade migration planning and execution require you draw
a comprehensive and accurate system diagram detailing the Cisco ICR/ICM
production system’s private and visible networks.

The private network is dedicated for Central Controller node communication and
used to establish, maintain, and restore synchronization between Central
Controller nodes. The private network must have sufficient bandwidth to
simultaneously handle traffic associated with the following:

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Synchronization of sides – side A and side B are synchronized in the event of
the failure of one side within a reasonable time

•

State transfer – data transfer from active side Router to the recovering side
router

The visible network is a Cisco shared network for local node communication and
remote node communication with the Central Controller. The visible network
must have sufficient bandwidth to support traffic associated with the following:

•

Active Directory synchronization

•

Logger database recovery

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Heartbeats – messages sent every 100 milliseconds to the CallRouter and the
PG to determine if they are “alive” or functioning.

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Report inquiries

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Alternate path by fault tolerant software to distinguish between node failures
and network failures.