May 21, 2018 · 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

Here we explore an IMS to PSTN terminating call. The call flow covers the IMS-ISUP interworking and Megaco/H.248 interactions between the MGCF and IM-MGW. Call routing via the BGCF is also illustrated. An IMS call is analyzed with a focus on the SDP interactions involved in codec selection and QoS.

May 7, 2018 · The IMS registration procedure includes the IMS authentication, e.g., IMS-AKA, and security negotiation between UE and IMS network. After successful IMS registration, the IMS network becomes aware of UE context such as subscription profile, registration status, etc.

After UE finishes radio procedures and it establishes radio bearers UE can start SIP registration towards the IMS for VoLTE call. Here is a typical IMS SIP registration call flow. The IMS client attempts to register by sending a REGISTER request to the P-CSCF.

Dec 2, 2022 · This document describes the VoLTE call flow for mobile originating and terminating calls using SIP over IMS. It outlines the key SIP messages and SDP exchanges involved in call setup, including the SIP INVITE, 100 Trying, 183 Session Progress, PRACK, UPDATE, 180 Ringing, 200 OK, and ACK messages.

Apr 22, 2013 · VoLTE MO and MT Call Flow :- Covering VoLTE to VoLTE SIP IMS Call flow for Mobile Originating & Mobile Terminating Calls .

May 21, 2018 · This document discusses the call flow process for a VoLTE call between two parties (A and B) using an LTE network. It involves the following key steps: 1. Party A's IMS network sends an SIP INVITE message to Party B's IMS network with an SDP offer to initiate the call. 2. Resources are reserved on the LTE networks for both parties.

Dec 23, 2016 · The simple way to know a call is Mo or MT is by checking the Direction header field in SIP INVITE message. If it is an MO call, the Direction header field should be UE to Network. And, for MT call the field must be NW to UE.

Mar 6, 2015 · We’ll put the LTE Packet Core part aside and take a look on the IMS related VoLTE architecture and VoLTE flows. Voice over LTE service specified in GSMA IR.92. If you think it seriously with VoLTE, don’t waste your time on any blog and read the VoLTE Service Description and Implementation Guide.

IMS to IMS Call Flow that focuses on interactions between the UE, the visited and the home IMS networks. This call flow describes the call setup between two IMS subscribers.