. Other components, such as the Virtual Network Function Manager, are responsible for the life cycle management of the Virtual Network Function (VNF); in this case, it's the virtual machine hosting 4G packet core network elements such as the Mobility Management Entity (MME), the PDN Gateway (PGW), and the Serving Gateway (SGW). The Element Manager (EM) is responsible for managing the individual VNFs. Cloud-native infrastructure and applications OSS/BSS Orchestrator Manager MME/SGSN S-PGW/GGSN Virtual Virtual Storage Virtual Network Virtual Computing Infrastructure Manager VIRTUALISATION LAYER COTS Hardware COTS Hardware COTS Hardware Appliance-Based Legacy Telecom Infrastructure Virtualized Infrastructure Figure 3.1 - ETSI MANO NFV architecture To summarize, the first major transformation of telecom applications came with virtualization. This started with 3G and 4G software between 2012 and 2016. This trend has now been taken forward and enhanced natively in 5G. Network functions and standards in 5G have incorporated the tenets of cloud and virtualization from the very beginning. It is recommended to architect 5G NFs on cloud-native development principles. Cloud-native software is built for reliability, consistency, and ease of scaling. The preceding 5G specifications have justified the adoption of cloud-native development principles. We will now go over the details of cloud native-based infrastructure in the next section. Cloud-native infrastructure and applications Cloud-native infrastructure removes the expensive proprietary appliance-based hardware used to run applications and replaces it with cheaper COTS hardware. With advancements in virtualization software, a network is also provided as a service. This improvement ushers in a whole new way of developing software as microservices. Containers are a cloud-native way of providing infrastructure to a cloud-native application. The runtime environment for executing code is provided by containers, which could contain images of the operating system and other custo