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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).