IMG 1010 - SIP PRACK Call Flows

Changes to Basic Call Flow with PRACK enabled

The call flow on the left highlights the changes when PRACK is enabled, as compared to the call flow on the right without PRACK enabled.

UAS Honors UAC’s Preference

This call flow shows the call flow when UAS and UAC are set to PRACK Supported option.

UAS Agrees to UAC’s Enforcement

This call flow shows when UAS and UAC are set to PRACK Require option.

UAS Ignores UAC’s Preference

This call flow shows the call flow when UAS is PRACK Supported and UAC is PRACK Disable.

UAS Rejects UAC’s Enforcement

This call flow shows the call flow when UAS is PRACK Require and UAC is PRACK Disable.

UAS Insists UAC MUST Support 100rel

This call flow shows the call flow when UAS is PRACK Disable and UAC is PRACK Require.

UAC Insists on Reliable Delivery of Provisional Responses

This call flow shows when UAS is configured with PRACK Require option.

IMG Acts as UAC and UAS

Basic Call Flow which includes the SDP message.

The IMG must include an SDP answer in the 200 OK to PRACK when an SDP offer is received in the PRACK request