- MBS User Services (MBSF, MBSTF, MBS Client, MBS-Aware Application, Application Provider): audited against the Release 17 to 20 specifications (the view opens at Release 20). The code is built against the Release 18 interfaces.
- MBS in the 5G System and NG-RAN: not yet audited.
- Source of this page: an audit of the
mainbranch of each repository on 2026-10-11: each requirement split into the cases its clause defines, each case read against the code by one reader and then independently by a second, with a third reading where they disagreed. Cases that reading the code cannot settle are not shown.
For what the specifications define, see the Technology page. For how to run the tools, see the Tutorials.
Implementation status
Open a feature, then a requirement, to see each case and why. Filter by component and release.
MBS User Services
- 5G Multicast Broadcast Services (MBS).
- MBSF (MBS Function): rt-mbs-function. Built against: Release 18.
- MBSTF (MBS Transport Function): rt-mbs-transport-function. Built against: Release 18.
- MBS Client (MBS Client (UE)): rt-mbs-client. Built against: Release 18.
- MBS-Aware App (MBS-Aware Application (dashboard)): rt-mbs-application.
- Provider (MBS Application Provider (portal)): rt-mbs-application-provider.
- Source: code on main read against every statement of the MBS User Services specifications on the project page, then every case read again independently by a second reader; disagreements settled by a third reading, otherwise not shown, 2026-10-11.
- Not shown: 800 further cases (a specification or code outside the audit that could not be read; it could not be settled by reading the code; the readers disagreed, so the case is not shown; the sentence applies to MBMS, which MBS does not use (MBS announces with TS 26.517); the sentence states no behaviour a component could meet).
✓ Implemented≠ Differs from the specification– Absent? Specification inconsistent: its text and its OpenAPI or tables disagreei Noted: observed, not a verdict against a clauseStatus notifications24 of 47 implemented · 2 differ · 21 absent
Time synchronization0 of 38 implemented · 38 absent
Object repair7 of 217 implemented · 1 differs · 208 absent · 1 where the specification is inconsistent
Application Layer FEC14 of 24 implemented · 10 absent
Security0 of 53 implemented · 53 absent
Service areas, location-dependent and multiplexed sessions4 of 14 implemented · 1 differs · 9 absent
Conformance profiles2 of 12 implemented · 4 differ · 6 absent
User Service Announcement107 of 225 implemented · 25 differ · 93 absent
Provisioning of MBS User Services386 of 662 implemented · 48 differ · 228 absent
Packet Distribution Method5 of 8 implemented · 1 differs · 2 absent
Object Distribution Method70 of 127 implemented · 23 differ · 34 absent
Distribution Session control in the MBSTF269 of 398 implemented · 42 differ · 87 absent
General aspects of APIs for MBS User Services27 of 72 implemented · 21 differ · 24 absent
Functional entities and reference points2 of 3 implemented · 1 absent
Procedures2 of 2 implemented
General22 of 27 implemented · 2 differ · 3 absent
MBS in the 5G System and NG-RAN
Not yet audited. The MB-SMF, MB-UPF, AMF, gNB and UE code for MBS is in forks of Open5GS and srsRAN; their READMEs state no MBS-specific status.
The full audit, with the code behind each verdict, is available to 5G-MAG members through Developer Tools.
Used with other projects
- FLUTE (rt-libflute): the MBSTF and the MBS Client use it for object delivery. See Content Delivery Protocols and Tools.
- 5GC Service Consumers (rt-5gc-service-consumers): the MBSF reaches the MB-SMF through its MB-SMF library. See 3GPP RAN and Core Platforms.