Section: 5.9.2.2 NRF security requirements
Content: The Network Repository Function (NRF) receives NF Discovery Request from an NF instance, provides the information of the discovered NF instances to the NF instance, and maintains NF profiles. The NRF receives from NF Service Consumers or SCPs access token requests for service consumption and provides authorization tokens. The NRF shall act as authorization server.The following NRF service-based architecture security requirements shall apply: NRF and NFs that are requesting service shall be mutually authenticated. NRF may provide authentication and authorization to NFs for establishing secure communication between each other.