4. Volte call flow – SIP Call Flow – IMS Call procedure

VoLTE MO and MT Call Flow :- Covering VoLTE to VoLTE SIP IMS Call flow for Mobile Originating & Mobile Terminating Calls . It Provides extract of 3GPP / GSMA Specs simplified way

Volte call flow

Originating Call Flow Sequence described in Video

SIP INVITE message : UE –to– IMS

SIP 100 Trying : IMS –to– UE

SIP 183 Progress SDP : IMS –to– UE

SIP PRACK : UE –to– IMS

SIP 200 OK PRACK : IMS –to– UE

SIP UPDATE SDP : UE –to– IMS

SIP 200 OK UPDATE : IMS –to– UE

SIP 180 Ringing : IMS –to– UE

SIP 200 OK INVITE : IMS –to– UE

SIP ACK : UE –to– IMS

5. SRVCC (Single Radio Voice Call Continuity) in VoLTE & Comparison with CSFB

Thank you Vikas Shokeen

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