The 5G Core is made of Network Functions, each offering services through service-based interfaces. A component that needs one of those services acts as the NF service consumer of it. The 5G Core Service Consumers libraries package that consumer side so that different 5G-MAG components can reuse it, for example an Application Function calling the PCF, or the MBS Function calling the MB-SMF. Only the Network Functions that 5G Media Streaming and 5G MBS use are covered.
The services consumed
| Network Function | Service | Specification | Service operations |
|---|---|---|---|
| PCF | Npcf_PolicyAuthorization | TS 29.514 V20.1.0 clause 4.2 | Create, Update, Delete, Notify, Subscribe and Unsubscribe (clauses 4.2.2 to 4.2.7) |
| BSF | Nbsf_Management | TS 29.521 V20.1.0 clause 4.2 | Register, Deregister, Discovery, Update, Subscribe, Unsubscribe and Notify (clauses 4.2.2 to 4.2.8) |
| MB-SMF | Nmbsmf_TMGI | TS 29.532 V20.0.0 clause 5.2.2 | TMGI Allocate and TMGI Deallocate (clauses 5.2.2.2 and 5.2.2.3) |
| MB-SMF | Nmbsmf_MBSSession | TS 29.532 V20.0.0 clause 5.3.2 | Create, Update, Release, ContextUpdate, StatusSubscribe, StatusUnsubscribe, StatusNotify, ContextStatusSubscribe, ContextStatusUnSubscribe and ContextStatusNotify (clauses 5.3.2.2 to 5.3.2.11) |
| NRF | Nnrf_NFDiscovery | TS 29.510 V19.8.0 clause 5.3.2 | NFDiscover, SCPDomainRoutingInfoGet, SCPDomainRoutingInfoSubscribe, SCPDomainRoutingInfoNotify and SCPDomainRoutingInfoUnSubscribe (clauses 5.3.2.2 to 5.3.2.6) |
What each library consumes
- PCF library (
libscpcf): an Application Function asks the PCF to change the network routing policy of the traffic flows of a UE's PDU session by creating an application session context, withNpcf_PolicyAuthorizationat reference point N5. - BSF library (
libscbsf): finds which PCF manages the PDU session of a UE, identified by its IP address, withNbsf_Management; the BSF itself is found by asking the NRF. - MB-SMF library (
libscmbsmf): allocates and deallocates TMGIs withNmbsmf_TMGI, and creates, modifies and destroys MBS Sessions and subscribes to their events withNmbsmf_MBSSession, at reference point Nmb1.
These three descriptions are those of the project's own README; the specifications above define the services.