ssarily the case of one or the other being used; it could be a mixture. With the NSA approach, there is a 5G gNB, which supports dual connectivity to a 4G eNB, which stands for Evolved Node B. So, the UE will be in communication with both RAN nodes together. It will have 4G radio connectivity to the eNB and 5G radio connectivity to the gNB. With the help of 5G radio connectivity, service providers can provide 5G services to their customers. In this approach, notice that the control connectivity goes back into the 4G EPC since the eNB is the primary RAN device in this architecture. So, this approach provides the benefits of 5G gNB with 5G RAN coverage. Alternatively, 5GC can also be utilized. In this approach, there is a gNB again and that gNB is in communication with a Next-Generation eNB (ng-eNB). The main difference is that the ng-eNB connects to the 5GC. But it's a similar scenario whereby dual connectivity is used with the gNB as a secondary device and the ng-eNB as a primary device or master device and that control comes from the 5GC down to the ng-eNB. Both these options are NSA. It depends on the service provider as to which approach they want to go for. The second option is SA, which is a pure 5G deployment. The UE is using the gNB and that gNB is connecting directly to the 5GC. 4G EPC (Evolved Packet Core) 5GC (5G Core Network) Standalone standalone ng-eNB standalone Figure 1.7 - 5G Radio Access Network deployment options Certainly, the NSA option is more straightforward to implement with a smaller investment. However, in the long term, network architectures and thus network deployments will be based on SA. 5G NR and NG-RAN NR and NG-RAN features To meet the requirements of IMT-2020, such as coverage, capacity, and data rates, there are some techniques and technologies that are employed. Let's look at these in detail. Dual connectivity In a typical network deployment, there are UEs in communication with RAN nodes and RAN nodes are connected to the core network through the control plane and user plane. In