Converged Core Architecture
The converged core solution provides a single unified platform and architecture based on SMI. The supporting architecture integrates the cloud native S-GW and SMF deployment with S5-c and cnSGW-C functionalities. The solution uses 3GPP defined SBA interfaces for policy and charging functions.
In the converged core architecture, the 4G and 5G capable UEs are anchored on the same control plane instance. The control plane instance provides the SMF + S5-c and cnSGW-C functionalities.
The handoffs between 4G and 5G access types are seamless for 5G capable devices. The handoffs from LTE to UTRAN (4G/5G <-> 3G/2G) are not seamless for 4G capable devices.
The following figure illustrates the network architecture supported in this release.

The user plane function deployed as part of this solution is a VPC-SI VM. It supports SGW-U, PGW-U, and UPF functionalities in the same instance and exposes the Sxa/Sxb/Sxab/N4 interfaces towards the control plane. The UPF also supports multiple CP instances (up to 4) simultaneously. The UPF deployment is VM-based.