For Cisco CallManager Express 3.2.1 and later, basic automatic call distribution (B-ACD) and auto-attendant (AA) service is available in order to provide this functionality:
Automatic answer of outside calls with greetings and menus that allow callers to choose the appropriate department or to dial known extensions
Managed call queues for hunt groups that route calls for different menu options
Tools to obtain call statistics
Call coverage features are used in order to ensure that all inbound calls to Cisco Unified CallManager Express are answered by someone, regardless of whether the called number is busy or does not answer.
Some single-dialed-number call-coverage features, such as hunt groups, can send inbound calls that dialed a single directory number to a pool of phone agents. Other features increase the chance that a call is answered, because they give it another chance for a connection if the dialed number is not available.
Multiple-dialed-number call-coverage features provide different ways for one person to answer inbound calls to multiple numbers.