How does the 5G Core network handle network slicing in virtualized and cloud-native environments?

Network slicing is a key feature of 5G technology that allows the creation of multiple virtual networks within a single physical network infrastructure. Each network slice is designed to meet specific requirements and cater to diverse use cases, such as enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC), and massive machine-type communication (mMTC). The 5G Core (5GC) network plays a crucial role in enabling and managing network slicing in virtualized and cloud-native environments. Here's a technical explanation of how this is achieved:

1. Service-Based Architecture (SBA):
   • The 5GC is built upon a service-based architecture, where network functions are decomposed into modular and independent services.
   • Each service performs a specific function, and these services communicate with each other using well-defined application programming interfaces (APIs) based on HTTP/2.
2. Network Function Virtualization (NFV):
   • NFV is a key aspect of virtualizing the 5G Core network. It involves replacing traditional, dedicated hardware appliances with software-based virtualized instances.
   • Network functions such as the Access and Mobility Management Function (AMF), Session Management Function (SMF), User Plane Function (UPF), etc., can be deployed as virtualized network functions (VNFs) running on cloud infrastructure.
3. Containerization and Orchestration:
   • Containerization technologies, such as Docker, and orchestration platforms like Kubernetes, are employed to encapsulate and manage VNFs in a lightweight and scalable manner.
   • Containers provide a consistent and isolated environment for running network functions, allowing for efficient resource utilization.
4. Network Slice Selection:
   • When a user initiates a service request, the 5G Core network dynamically selects an appropriate network slice based on the specific requirements of the service (e.g., bandwidth, latency, reliability).
   • The selection is often driven by policies defined by the network operator and is performed by the Network Slice Selection Function (NSSF).
5. Network Slice Instance:
   • Once a network slice is selected, the 5G Core creates a specific instance of that slice, which includes the instantiation of the necessary VNFs and the allocation of resources.
   • The Network Slice Instance (NSI) ensures that the slice meets the performance and service-level objectives.
6. Slice-specific Network Functions:
   • Each network slice has its own set of network functions tailored to the requirements of the slice. For example, a slice designed for URLLC may prioritize low latency and high reliability, requiring specific configurations in the UPF and SMF.
7. Dynamic Resource Allocation:
   • The 5G Core network continuously monitors the performance of each network slice and dynamically allocates resources based on real-time demand.
   • This dynamic resource allocation ensures that each slice receives the necessary resources to maintain optimal performance.
8. End-to-End Network Slicing:
   • Network slicing extends from the radio access network (RAN) to the core network, providing end-to-end isolation and customization of services.
   • The 5G Core network collaborates with the RAN to ensure that the entire communication path aligns with the requirements of the selected network slice.