SBA API security: OAuth 2.0 for NF authorization

Securing Service-Based Interfaces

In the 5G service-based architecture, network functions communicate via HTTP/2 APIs rather than traditional point-to-point interfaces. This means any NF can potentially call any other NF's API, creating a critical need for robust authorization. 3GPP adopted OAuth 2.0, the industry-standard authorization framework, to control which NFs can access which services. The NRF serves dual duty as both the service discovery registry and the OAuth 2.0 authorization server, issuing and validating access tokens for all NF-to-NF communication across the service-based core.