he gateway is the option that can perform Call Progress Analysis (CPA) in outbound IVR. CPA is a DSP algorithm that analyzes the RTP voice stream to look for special information tones (SIT), fax or modem tones, human speech, and answering machine tones. CPA also passes the voice information to Cisco IOS or CUBE. CPA is initiated on receiving a new SIP INVITE with x-cisco-cpa content. The gateway detects non-live contact with its CPA capabilities and sends the status of the non-live contact to the dialer. The dialer then decides whether to redirect the call to UCCX or terminate the call based on the CPA event. References: Cisco Unified Border Element Configuration Guide - Cisco IOS XE 17.6 Onwards - Call Progress Analysis, IVR-Based Outbound Dialer Troubleshooting