What is `push versus `pull mechanism?
•Push—Cisco Unified CallManagers 5.x sends (pushes) data to Service Monitor. (Before this can happen, Service Monitor must be configured as a billing server. For more information, see Cisco Unified CallManager Configuration section of User Guide for Cisco Unified Service Monitor.) •Pull—Service Monitor periodically connects to Cisco Unified CallManagers 3.x and 4.x to obtain (pull) Call Data Records (CDRs) and Call Management Records (CMRs).