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3262 - Reliability of Provisional Responses in the Session Initiation Protocol (SIP)
Configuration
IMG 1010 - SIP Profile - 10.5.3
IMG 1010 - SIP PRACK Call Flows
Diagram - SIP PRACK Handshake
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Verify PRACK is enabled in the SIP SGP (see IMG 1010 - SIP Profile - 10.5.3)
Verify sure the correct SIP SGP is assigned to the External Gateway
Verify External Gateway must support PRACK.
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