Section: 4.5.1.8 MM connection establishment due to SRVCC or vSRVCC handover
Content: An MM connection can be established locally in the MS due to an SRVCC or vSRVCC handover (see 3GPP TS 23.216[ Single Radio Voice Call Continuity (SRVCC); Stage 2 ]  [126]), i.e. without dedicated MM signalling. That is the case when the MS has: - a voice media stream carried over the PS domain that is handed over to the CS domain in A/Gb mode or Iu mode via SRVCC; - a voice media stream and a video media stream of a single session carried over the PS domain in S1 mode that is handed over to the CS domain in Iu mode via vSRVCC; - a voice media stream and a video media stream of a single session carried over the PS domain in S1 mode but only the voice media stream is handed over to the CS domain in A/Gb mode via SRVCC; or - a voice media stream carried over the PS domain in N1 mode that is handed over to the CS domain in Iu mode via 5G-SRVCC handover from NG-RAN to UTRAN. An MS in MM state MM IDLE shall establish the MM connection locally when it receives an indication from lower layers that either a voice only SRVCC handover or a voice and video SRVCC handover was completed successfully. After completing MM connection establishment, the MM layer shall indicate "MM connection establishment due to SRVCC handover" or "MM connection establishment due to vSRVCC handover" to the upper layer and shall enter state MM CONNECTION ACTIVE.