Call flows 5G-NR Non Standalone Access Flow (EN-DC) LTE support for 5G dual connectivity will enable 4G network operators to introduce 5G services with a minimal upgrade to support 5G data plane. This is achieved with the support for 4G eNB and 5G gNB dual connectivity (EN-DC). ...
The caller and the called user require resource reservation before the call can be setup. The major steps in the call flow are: IMS routing of the initial SIP INVITE. IMS routing of the first response to the INVITE. Resource allocation via PDP context activation. ...
This call flow describes the call setup from an IMS subscriber to ISUP PSTN termination. The call is routed via the BGCF (Border Gateway Control Function) to the MGCF (Media Gateway Control Function). The MGCF uses one context with two terminations in IM-MGW (Media Gateway). The termination...
Describes the complete flow of circuit switched fallback from an LTE network to UMTS. You can click on most messages in the flow to reveal full details about individual messages. Interactions between LTE and 3G Summary call flow that focuses on the interactions between 4G and 3G networks for ...