Reference implementation of the 5G Multicast Broadcast Services (MBS) user service layer targeting 3GPP Release 17 and 18.
Unlike LTE-based 5G Broadcast (evolved Multimedia Broadcast Multicast Service, eMBMS), 5G MBS is natively integrated into the 5G Core (5GC) and New Radio (NR) Radio Access Network (RAN), enabling efficient point-to-multipoint delivery of live TV, software updates, and emergency information. The tools cover MBS service announcements, session management, and media delivery over the broadcast delivery mode, as defined in TS 26.502, though the chain does not yet run fully end-to-end on real RAN hardware or software radio today; the multicast delivery mode's MB-SMF/MB-UPF data path already exists, but its session-join control plane does not yet (see Scope for the detail on both).
If you are looking for the LTE-based, free-to-air broadcast implementation (a separate, similarly named area), see the 5G Broadcast reference tools instead.
Implemented specifications: 3GPP TS 26.502 (MBS user services), TS 23.247 (MBS architecture and functional description), TS 38.300 (NR overall description, RAN broadcast procedures), TS 29.580 (MBSF services, Nmb10), TS 29.581 (MBSTF services, Nmb2/Nmb8/Nmb9), TS 29.532 (MB-SMF services, Nmbsmf_TMGI/Nmbsmf_MBSSession).
Contributors
Project Overview
The slide deck below introduces the 5G MBS reference tools, their architecture and the specifications they implement.
Download the slide deck of this ProjectGo deeper
| Area | Details |
|---|---|
| Technical documentation | Architecture, RAN aspects, and mobility analysis: 5G Multicast Broadcast Services (MBS) on the Tech portal |
| Standards | Normative specs and 5G-MAG contributions: 5G Multicast Broadcast Services (MBS) on the Standards portal |
| Applications | Real, assembled scenarios built on this tool: MBS End-to-End Delivery Demo |
| Implementation Blueprints | The step-by-step procedures this tool implements: MBS Broadcast RAN acquisition, MBS Multicast RRC_INACTIVE RAN acquisition, MBS Multicast mobility, MBS Service Layer provisioning-to-announcement |
Developer Exchange
See the reference tools in action in this community video.
Connecting MBSTF to the MBS System - Developer Exchange
Community Stats
Last Synced: 2026-09-11 01:35 UTC
| Repository | Stars | Forks | Views (Total) | Clones (Total) | Activity |
|---|---|---|---|---|---|
| rt-mbs-function | 2 | 3 | 1029 | 1105 | Active |
| rt-mbs-transport-function | 1 | 3 | 562 | 513 | Active |
| rt-mbs-examples | 10 | 9 | 1617 | 510 | Active |
| rt-common-shared | 3 | 8 | 398 | 1692 | Active |
| rt-libflute | 23 | 13 | 700 | 2059 | Active |
| open5gs | 5 | 8 | 562 | 1121 | Active |
| srsRAN_4G | 5 | 2 | 112 | 42 | Quiet |
| rt-srsRAN_Project | 4 | 3 | 319 | 228 | Quiet |
| rt-mbs-application-provider | 0 | 0 | 29 | 2 | Active |
| rt-mbs-client | 0 | 0 | 108 | 12 | Active |
| rt-mbs-application | 0 | 0 | 32 | 2 | Active |