ment. This accounts for automobiles that are often on the move. In the bottom slice, geared toward IoT devices, mMTC allows for very high connection densities. Usually, the data rate may be low from such IoT devices. Mobility management is not needed for this slice. User Equipment Base Station Edge Cloud Core Cloud Charging Mobility Cache Session Slice Access URLLC Server Session Charging Slice Access Mobility Session Charging Slice Access Mgmt Server SDN Controller NFV Orchestrator Figure 13.9 - Network slicing architecture view Network slicing architecture and design Let us next look at the 3GPP architecture for 5G network slicing. We will list out the relevant acronyms here: Network Slice Selection Function (NSSF) Access and Mobility Management Function (AMF) Network Repository Function (NRF) Session Management Function (SMF) User Plane Function (UPF) Policy Control Function (PCF) Data Network (DN) Figure 13.10 shows how the common network functions, and those unique to each of the two slices, are invoked to create two DNs with unique network characteristics. Slice 1 Common NFs Slice 2 Figure 13.10 - 3GPP architecture for 5G network slicing Figure 13.10 shows the power of network slicing and its ability to work with DNs best suited for the use case. Architecture and flow diagram The key tenet of the 5G network slicing architecture is the complete logical isolation from other slices in an end-to-end (E2E) network. Traditional software design concepts such as virtualization and recursion play a key role in network slicing. The concept of recursion is utilized through SDN, which enables the control plane to support the specific slice composition by creating several sub-controllers. NFV facilitates the network functionality on Virtual Machines (VMs) to easily decouple the slice building blocks from propriety hardware components, adding to the agility of the network slice design. This speeds up the provisioning of the network slices (for more information, visit https : / / www. viavisolutions.com/en-us/5g-network-s