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HTTP API Dictionary (SBI Service API)

A dictionary for looking up the key service APIs each NF offers over the SBI (Service Based Interface) by providing NF, use, and related reference point. All operate over HTTP/2 + JSON over TLS.

Related: Protocol Dictionary / NF Dictionary / Interface Dictionary / Registration chapter


SBI service API list

Service API Providing NF Main use Related reference point Spec
Namf_Communication AMF NAS/N2 message exchange, inter-AMF coordination (representative operations illustrated; details to be confirmed) N11 / N14 TS 29.518
Namf_EventExposure AMF Exposure of events such as mobility (details to be confirmed) TS 29.518
Nsmf_PDUSession SMF PDU session control (Create/Update/ReleaseSMContext, etc.; illustrative) N11 TS 29.502
Nudm_UECM UDM Serving NF registration management (details to be confirmed) N8 TS 29.503
Nudm_SDM UDM Subscription data retrieval and change notification (details to be confirmed) N8 / N10 TS 29.503
Nudm_UEAuthentication UDM Authentication information provision (details to be confirmed) N13 TS 29.503
Nausf_UEAuthentication AUSF UE authentication (5G-AKA / EAP-AKA'; details to be confirmed) N12 TS 29.509
Npcf_SMPolicyControl PCF SM policy / PCC rule (details to be confirmed) N7 TS 29.512
Npcf_AMPolicyControl PCF AM policy (details to be confirmed) N15 TS 29.507
Npcf_PolicyAuthorization PCF Policy authorization of AF requests (details to be confirmed) N5 TS 29.514
Nnrf_NFManagement NRF NF registration / update / deregistration (details to be confirmed) TS 29.510
Nnrf_NFDiscovery NRF NF discovery (details to be confirmed) TS 29.510
Nnssf_NSSelection NSSF Slice selection (details to be confirmed) N22 TS 29.531
Nnef_* (capability exposure family) NEF Capability exposure Northbound API (operation set; details to be confirmed) N33 TS 29.522
Nudr_DataRepository UDR Data persistence (details to be confirmed) N35 / N36 / N37 TS 29.504
Nchf_ConvergedCharging CHF Converged charging (details to be confirmed) N40 TS 32.290
Nsmsf_SMService SMSF SMS over NAS (details to be confirmed) N20 TS 29.540
Nnwdaf_AnalyticsInfo / EventsSubscription NWDAF Data analytics (details to be confirmed) TS 29.520
Nbsf_Management BSF Session⇔PCF binding management (details to be confirmed) TS 29.521

Reference points and services are two views of the same thing

In SBI, "reference point Nxx (e.g., N8)" and "service Nxxx (e.g., Nudm)" refer to the same inter-NF coordination under different names. Each API commonly operates over HTTP/2 + JSON over TLS (TS 29.500 defines the framework), and the destination is resolved by the NRF's NFDiscovery, so do not assume a fixed listening port. For the specifics of resource URIs, HTTP method assignments, and operation details, refer to the relevant chapters of each TS (this dictionary is for indexing purposes).