Testing NFs — unit, integration, conformance with gNB simulators

Three Layers of NF Testing

A production NF needs three layers of test coverage. Unit tests verify individual functions and state transitions in isolation, with all external dependencies mocked. They run in milliseconds and catch logic bugs early. Integration tests run multiple NFs together (often in Docker Compose or a small Kubernetes cluster) and exercise interactions across SBI — for example, AMF + AUSF + UDM + SMF + UPF integration with a simulated gNB and UE. They run in seconds to minutes and catch interaction bugs. Conformance tests issue 3GPP-specified protocol exchanges and verify the NF behaves exactly as the…