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TS 24.228 – §7.2.2 – §7.3.2 – §7.4.2   List   Prev   Next
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IMS S1 signalling flow - Session Initiation: Mobile origination and termination roaming, with different network operators - sequence chart for IMS S1-1. SIP INVITE request (UE1 to UE2)
  • UE1 is located in a visited network, and determines P-CSCF1 via the CSCF discovery procedure.
  • P-CSCF1 knows the name/address of S-CSCF1 from a prior Registration performed by the UE.