Voice Calls Using CAP4 Protocol

Message sequences for voice calls using the CAMEL Application Part 2 (CAP2), CAP3, and CAP4 protocols are usually the same. However, CCF handles the following exceptions to message sequences for voice calls using the CAP4 protocol:

  • For CAP4, MATRIXX Engine returns a TCAP CONTINUE(ReleaseCall) message to the Mobile Switching Center (MSC) after it receives a TCAP CONTINUE(ACR(callLegReleasedAtTcpExpiry)) message from the MSC. If you configure CCF to send CallInformationRequest (CIQ) operations, MATRIXX Engine must send a TCAP CONTINUE(ReleaseCall) message before receiving the CallInformationReport operation in a TCAP CONTINUE message from the MSC.
  • MATRIXX Engine can send an ApplyCharging operation to the MSC that has the tone parameter; for example, if the subscriber runs out of funds. For CAP4, MATRIXX Engine sends an ApplyCharging operation containing the audibleIndicator.tone parameter instead.
  • MATRIXX Engine can also take account of the CAP4 chargeIndicator parameter in EventReportBCSM.oAnswerSpecificInfo or EventReportBCSM.tAnswerSpecificInfo operations when deciding whether to charge for a call.