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Introduction to TUP Call Control
Overview
The host manages TUP call control and circuit management through the following mechanisms:
• Common Call Control API messages, using Formatted Fields (TUP) ICBs to pass data.
• Channel State
DS0 Status Change messages notify the host of service state changes and channel purges. The Service State Configure message allows the host to bring channels in and out-of-service.
• The PPL Event Indication and PPL Event Request messages allow the host to send and receive messages to and from PPL components. See SS7 PPL Information for events supported per component.
The Excel platform sends PPL Event Indication messages to the host in response to various SS7-related call processing events, such as reception of an ACM, ANN, ANU, ANC in the case of TUP, and ACF (ACT/ACS/ACP/ALT/ALS/ALP) and RIU in the case of TUP SSUTR2.
,Data is included in the SS7 TUP Formatted Fields ICB. If you do not require this information, Acknowledge (ACK) the message and then ignore it.
The host can generate SS7-related call processing or management events using the PPL Event Request message.
You can modify the default call model to have the Called and Calling Party Numbers passed to the host as BCD encoded digits. SCCP/TCAP for more information (CSP-only).