Cisco Cisco Unified Contact Center Enterprise 9.0(2) Maintenance Manual

Role of the Synchronizers

The Synchronizers play the key role in maintaining synchronized execution across the two sides
of the Central Controller. All input for the CallRouter and any changes to the Logger must pass
through the Synchronizers.

Each time a Synchronizer receives input, it passes that input to its duplicate on the other side.
The two Synchronizers cooperate to ensure that they are both sending the same input to the
Central Controllers on both sides of the system.

The following figure shows how the Synchronizers combine input messages and send the
messages in the same order to each side of the Central Controller.

Figure 4: Role of the Synchronizers

Both CallRouters receive the same input and generate the same output. The Synchronizers
ensure that both sides of the Central Controller return identical destinations for the same call
and write identical data to the databases.

The following figure further illustrates the Central Controller and its device connections.

Administration Guide for Cisco Unified ICM/Contact Center Enterprise & Hosted Release 8.x