Introduction
The SIP trunk integration is a method to establish communication between Unity Connection and Cisco Unified CM using SIP protocol.
For a list of supported versions of Cisco Unified CM that are qualified to integrate with Cisco Unity Connection through a SIP trunk, see the Compatibility Matrix for Cisco Unity Connection at http://www.cisco.com/c/en/us/support/unified-communications/unity-connection/products-device-support-tables-list.html.