Communications Manager formerly CallManager is the application foundation of the Unified Communications infrastructure.  This component provides traditional telephony features as well as the foundation for advanced features such as presence, mobility, preference, and rich media collaboration.

The comparable traditional telephony component would be the PBX (Private Branch Exchange) or key system.  These are the traditional telephone systems that have been around for decades and are now being replaced at a rapid rate with new yet mature and emerging  technology such as Cisco's Unfired Communications Manager.  It is a known fact that Cisco is now the leader in the telephony market space and is displacing the likes of Avaya and Nortel.

The Communications Manager can be clustered to provide a highly available system supporting over 30,000 users in a single cluster.  The list of features is lengthy to say the least.  This list can be found at the following location by clicking here .  In addition to the reliability and feature depth we can also say that Cisco haves dedicated their its efforts to developing all the Unified Communications (UC) towards an open standard.   This allows for a consistent experience across all platforms and the ability for third party partners to integrate into these applications as well thus providing additional value add.

In summary, this component of the Unified Communications infrastructure is responsible for call processing and related features.  It can also be seen to provide the "now" factor where customers can make the necessary changes required for end users when they are ready and available to do so.  This is a significant jump forward in productivity and cost reduction.    Traditionally customers would have paid a fee for the Install, move, add or change (IMAC) and additionally would have had to rely on the provider to make these changes.  Also, the customer would have been at the mercy of that provider's scheduling and availability.  The empowerment that the customer now possesses is that they can realize the added value and functionality that cannot be achieved with closed systems.