Network Resource Director

The Network Resource Director (NRD) is a critical component for managing and discovering network resources efficiently in a 5G environment. It is defined as a system that supports 3GPP services for Network Resource Discovery and Network Slice Selection Function. It utilizes containers and pods on x86 servers to enable horizontal scaling of network functions. The NRD architecture includes various Network Function components such as OAM for management interfaces, KPI-KCI for report generation, NRD for NF management services, Discovery for NF discovery services, NSSF for NS selection services.

The 5G core network uses a Service-Based Architecture (SBA), where various Network Functions (NFs) interact through a common protocol based on OpenAPI v3, using JSON over HTTP/2. Each NF can have multiple instances, identified by a unique Network Function Instance ID (NFInstanceID), modeled as a UUID. Communication between these functions relies on services offered by each function, with a service producer (server) and a service consumer (client) executing specific tasks. Interfaces, like N11, consist of multiple services, such as Nsmf_PDUSession and Namf_Communication, where different functions act as servers. This approach, known as Service-Based interfaces (SBi), allows services to be reused across interfaces, enhancing flexibility, scalability, and modularity in the network, supporting applications like IoT and edge computing.