etwork. What that essentially means is the separation of control and data plane across the network in the various nodes. The key nodes here are the SGW and Packet Network Data Gateway (PGW) in the 5G Non-Standalone Networks EPC, to be split into SGW-c, SGW-u, PGW-c, and PGW-u. Similarly, on the radio side, CUPS can be achieved. The reason behind this design choice is to make more processing power available to support faster data rates by decoupling control plane responsibilities, hence resulting in a faster speed. Virtualization has been key in network function implementation since the beginning of the last decade. It was successfully adopted in later deployments of 4G networks where the appliance-based network elements were migrated to virtualized ones. This not only reduced the CAPEX but also increased capacity in the network, as deployments were now commercially available off the shelf, as compared to the earlier expensive custom appliance-based deployments, but it also reduced the time to market as it adopted advanced orchestration and network automation techniques for deployment. Now, considering the favorite choice of operators has been to start with option 3 for initial rollouts of 5G, let us go over the various migration paths available to them, as shown in the following table: Use Cases Support Key Aspects EPS to SA option 2 Full set of 5G use cases Small impact on existing 4G network Efficiencies of 5G core can be leveraged The legacy 4G network needs to be retained 4G-5G interworking will be required to support seamless mobility Voice can be supported via IMS EPS to NSA option 3 Limited support for 5G use cases Leverage existing LTE network Rapid time to market Features limited to 4G core, hence advancements of 5G core are absent Procedures are based on EPC Voice can be supported by existing VoLTE infrastructure A deep dive into NSA networks NSA option 3 to NSA All 5G use cases can be supported Migration of core network option 4/SA option 5 should be accounted for 5G core benefits can be leveraged EPC 