-Centric Common Management 5G Next Generation Core Network 5G Radio Access Fixed Access Technology (RAT) Evolved-LTE Wi-Fi New Radio (NR) RAT (eLTE) Figure 12.2 - 5G Architecture The NVFI utilizes Intel x86 or generic computing hardware, which is easy to obtain and maintain as organizations' IT departments are well versed in it. The software stack includes the following elements: Hypervisors Virtual Machines (VMs) Virtual Infrastructure Managers This provides the physical and virtual network layers for 5G. Together it creates the layer of the physical hardware stack for the compute, storage, and network. This is the software foundation for the deployment and management of VNFs. The NVFI facilitates the virtualization layer over the hardware layer. In other words, the NVFI provides an abstraction layer of the x86 hardware servers. It allows logical partitioning and provisioning for the VNFs to operate smoothly. In addition, the NFVI helps to expand the geographical span over the prior-generation network architectures. Next, let us look at Software-Defined Networking (SDN). The role of SDN In 5G networks, SDN and NFV provide software-based management and programmable control of network resources. SDN and NFV also enable network slicing in 5G to allow multiple isolated logical networks, catering to different services. These logical networks of different capacities and properties 5G Infrastructure Design fulfill the need for different requirements, such as smartphones, Internet of Things (IoT) devices, and emerging needs of autonomous vehicles or drones. Cisco defines SDN as the ability to program the network and drive automation. SDN can also be considered as creating the physical separation of the network/user plane from the control plane. A commonly used protocol for SDN is OpenFlow, which provides communication between the control layer and the infrastructure layer. Other protocols often used are NETCONF, Border Gateway Protocol Link-State (BGP-LS), Simple Network Management Protocol (SNMP), or Application Policy