ETSI TS 123 246 V15.1.0 (2019-10)

Universal Mobile Telecommunications System (UMTS); LTE; Multimedia Broadcast/Multicast Service (MBMS); Architecture and functional description (3GPP TS 23.246 version 15.1.0 Release 15)

RTS/TSGS-0223246vf10

General Information

• Status: Published
• Publication Date: 30-Sep-2019
• Technical Committee: 3GPP SA 2 - Architecture
• Current Stage: 12 - Completion
• Completion Date: 01-Oct-2019

Standards Content (Sample)

TECHNICAL SPECIFICATION
Universal Mobile Telecommunications System (UMTS);
LTE;
Multimedia Broadcast/Multicast Service (MBMS);
Architecture and functional description
(3GPP TS 23.246 version 15.1.0 Release 15)

3GPP TS 23.246 version 15.1.0 Release 15 1 ETSI TS 123 246 V15.1.0 (2019-10)

Reference
RTS/TSGS-0223246vf10
Keywords
LTE,UMTS
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ETSI
3GPP TS 23.246 version 15.1.0 Release 15 2 ETSI TS 123 246 V15.1.0 (2019-10)
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3GPP TS 23.246 version 15.1.0 Release 15 3 ETSI TS 123 246 V15.1.0 (2019-10)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 6
1 Scope . 7
2 References . 7
3 Definitions and abbreviations . 8
3.1 Definitions . 8
3.2 Abbreviations . 9
4 MBMS Architecture . 9
4.1 Overview . 9
4.2 Reference Architecture Model . 10
4.2.1 GPRS . 10
4.2.2 EPS . 10
4.3 MBMS Specific Reference points . 11
4.3.1 Gmb . 11
4.3.1a SGmb . 11
4.3.2 Mz . 11
4.3.3 Reference Points for Evolved Packet System . 12
4.4 MBMS Service Provision . 12
4.4.1 MULTICAST MODE . 12
4.4.1.1 Subscription . 14
4.4.1.2 Service announcement . 14
4.4.1.3 Joining . 15
4.4.1.4 Session Start . 15
4.4.1.5 MBMS notification . 15
4.4.1.6 Data transfer . 15
4.4.1.7 Session Stop . 15
4.4.1.8 Leaving . 15
4.4.2 Multicast Mode timeline . 15
4.4.2.1 Period between Service Announcement and Session Start . 15
4.4.2.2 Period between Service Announcement and Service Subscription . 15
4.4.2.3 Period between Service Announcement and Joining . 16
4.4.2.4 Period between Joining and Session Start . 16
4.4.2.5 Period between Session Start and First Data Arrival . 16
4.4.2.6 Period between Session Start and Session Stop . 16
4.4.2.7 Session Update . 16
4.4.3 BROADCAST MODE . 16
4.4.3.1 Service announcement . 18
4.4.3.1a UE local service activation . 18
4.4.3.2 Session Start . 18
4.4.3.3 MBMS notification . 18
4.4.3.4 Data transfer . 18
4.4.3.5 Session Stop . 19
4.4.3.6 Session Update . 19
4.4.4 Broadcast Mode timeline . 19
4.4.4.1 Period between Service Announcement and Session Start . 19
4.4.4.2 Period between Session Start and First Data Arrival . 19
4.4.4.3 Period between Session Start and Session Stop . 19
5 Functional Entities To Support MBMS . 19
5.0 General . 19
5.1 Broadcast-Multicast Service Centre (BM-SC) . 19
5.1.0 General . 19
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5.1.1 Membership Function . 20
5.1.2 Session and Transmission Function . 20
5.1.3 Proxy and Transport Function . 21
5.1.4 Service Announcement Function . 21
5.1.4a MBMS Security Function . 22
5.1.5 MBMS Content Transfer for the same MBMS User Service for GPRS and EPS . 22
5.1.5.1 General . 22
5.1.5.2 Separate MBMS Bearer Services for the same MBMS User Service . 22
5.1.5.3 Same MBMS Bearer Service for the same MBMS User Service . 23
5.1.6 Location Dependent Content Transfer for the same MBMS User Service (Broadcast Mode only) . 23
5.1.7 MBMS User Service Consumption Reporting (Broadcast mode only) . 23
5.2 User Equipment . 24
5.3 UTRAN/GERAN . 24
5.4 SGSN . 24
5.5 GGSN . 25
5.6 MBMS Data Sources and Content Provider . 25
5.7 Other Functional Element . 25
5.7.1 Void . 25
5.7.2 CBC . 26
5.7.3 Void . 26
5.8 Void . 26
5.9 Functional Elements for the Evolved Packet System . 26
5.9.1 MBMS GW . 26
5.9.2 MBMS Control plane function . 27
5.9.3 E-UTRAN . 27
6 MBMS Attributes and Parameters . 27
6.1 MBMS UE Context . 27
6.2 MBMS Bearer Context . 28
6.3 Quality-of-Service . 31
6.3.1 Quality-of-Service for GPRS . 31
6.3.2 Quality-of-Service for EPS . 32
6.3.3 MBMS QoS distribution tree . 33
6.4 Temporary Mobile Group Identity . 34
6.5 IP Multicast distribution . 34
6.5.1 General . 34
6.5.2 IP Multicast distribution for GERAN Iu-mode and UTRAN for GPRS . 34
6.5.3 IP Multicast distribution for E-UTRAN and UTRAN for EPS . 35
7 Architectural Aspects of MBMS User Services . 35
7.1 Alternative User Service Support . 36
7.2 Avoid overload in SGSN, GGSN and BM-SC caused by Joining . 36
7.3 Access aspects of MBMS user services . 36
7.4 MBMS operation on Demand . 36
7.5 Enhanced TV services support over E-UTRAN . 36
8 MBMS Procedures . 37
8.1 MBMS Notificatio n . 37
8.1.1 Iu mode notification (UTRAN and GERAN) for GPRS. 37
8.1.2 A/Gb mode notification (GERAN) . 38
8.2 MBMS Multicast Service Activation . 38
8.2.1 Void . 40
8.3 MBMS Session Start Procedure . 40
8.3.0 General . 40
8.3.1 MBMS Session Start Procedure for GERAN and UTRAN for GPRS . 41
8.3.2 MBMS Session Start Procedure for E-UTRAN and UTRAN for EPS . 42
8.4 MBMS Registration Procedure . 45
8.5 MBMS Session Stop Procedure . 47
8.5.0 General . 47
8.5.1 MBMS Session Stop Procedure for GERAN and UTRAN for GPRS . 47
8.5.2 MBMS Session Stop Procedure for E-UTRAN and UTRAN for EPS . 48
8.6 MBMS De-Registration Procedure . 49
8.6.0 Common MBMS De-Registration procedure . 49
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8.6.1 BM-SC initiated MBMS De-Registration Procedure . 50
8.7 MBMS Multicast Service Deactivation . 51
8.8 MBMS Session Update procedure . 53
8.8.1 General . 53
8.8.2 SGSN initiated Session Update for GERAN and UTRAN for MBMS Multicast service . 54
8.8.3 BM-SC initiated Session Update for GERAN and UTRAN for MBMS Broadcast service . 54
8.8.4 BM-SC initiated Session Update for EPS with E-UTRAN and UTRAN . 55
8.9 MBMS UE Context Synchronisation Procedure . 58
8.9a MBMS feature support indication . 58
8.10 Inter SGSN Routeing Area Update . 59
8.10a Inter-system Intra-SGSN change . 60
8.11 Inter SGSN Serving RNS Relocation Procedure . 60
8.12 MBMS Broadcast Service Activation . 62
8.13 MBMS Broadcast service de-activation . 62
8.14 Void . 62
8.15 MBMS UE Linking/De-linking mechanism . 62
8.16 MBMS Service Request Procedure . 63
8.17 Notification in case of parallel services . 64
8.17.1 Notification of incoming CS domain call during an ongoing MBMS session . 64
8.17.2 Notification of additional MBMS session during an ongoing MBMS session . 64
8.17.3 Notification of Mobile Terminating PS data during an ongoing MBMS session . 64
8.17.4 Notification of MBMS session during an ongoing CS or PS domain "connection" . 64
9 Security. 65
10 Charging requirement . 65
10.1 General . 65
10.2 Bearer level charging for MBMS . 65
10.3 Application level charging for MBMS . 65
10.4 Generation of charging records in the VPLMN . 66
11 Roaming Support for MBMS user services. 66
11.1 Scenarios description . 66
11.2 Scenario signalling flow . 66
11.2.1 APN selection . 66
Annex A (Informative): Void . 68
Annex B (Informative): Void . 69
Annex C (normative): TV services delivery using unicast mode & switching between
broadcast & unicast modes for E-UTRAN . 70
Annex D (normative): Shared MBMS Network over E-UTRAN . 72
D.1 General . 72
D.2 Architecture . 72
D.2.1 Architecture for per PLMN MBSFN synchronization area . 72
D.2.2 Reference Points . 73
D.2.3 UE Aspects . 73
D.2.4 TMGI for shared MBMS networks . 74
Annex E (normative): UE behaviour in Receive Only Mode . 75
Annex C (Informative): Change history . 77
History . 78

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3GPP TS 23.246 version 15.1.0 Release 15 6 ETSI TS 123 246 V15.1.0 (2019-10)
Foreword
This Technical Specification has been produced by the 3rd Generation Partnership Project (3GPP).
The contents of the present document are subject to continuing work within the TSG and may change following formal
TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.
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3GPP TS 23.246 version 15.1.0 Release 15 7 ETSI TS 123 246 V15.1.0 (2019-10)
1 Scope
The present document describes the stage 2 description (architectural solution and functionalities) for the MBMS Bearer
Service, which includes, together with MBMS User Services defined in TS 26.346 [7], all the elements necessary to
realise the stage 1 requirements in TS 22.146 [2] and TS 22.246 [6]. This document encompasses both GPRS and EPS.
The present document also includes considerations on the manner in which User Services should make use of the
MBMS Bearer Service described herein. It should be noted that the specification of MBMS User Services in
TS 26.346 [7] takes precedence over User Service aspects described in this document.
The present document includes information applicable to network operators, service providers and manufacturers.
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
- For a specific reference, subsequent revisions do not apply.
- For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including
a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
Release as the present document.
[1] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] 3GPP TS 22.146: "Multimedia Broadcast/Multicast Service; Stage 1".
[3] 3GPP TS 23.107: "Quality of Service (QoS) concept and architecture".
[4] 3GPP TS 29.061: "Interworking between the Public Land Mobile Network (PLMN) supporting
packet based services and Packet Data Networks (PDN)".
[5] 3GPP TS 33.246: "Security of Multimedia Broadcast/Multicast Service".
[6] 3GPP TS 22.246: "Multimedia Broadcast/Multicast Service (MBMS) user services".
[7] 3GPP TS 26.346: "MBMS: Protocols and Codecs".
[8] void.
[9] void.
[10] 3GPP TS 25.346: "Introduction of the Multimedia Broadcast Multicast Service (MBMS) in the
Radio Access Network".
[11] 3GPP TS 43.246: "Technical Specification Group GSM/EDGE Radio Access Network;
Multimedia Broadcast Multicast Service (MBMS) in the GERAN".
[12] 3GPP TS 23.125: "Overall high level functionality and architecture impacts of flow based
charging; Stage 2".
[13] 3GPP TS 23.003: "Numbering, addressing and identification".
[14] 3GPP TS 32.422: "Subscriber and equipment trace; Trace control and Configuration Management
(CM)".
[15] 3GPP TS 23.060: "General Packet Radio Service (GPRS); Service description; Stage 2".
[16] 3GPP TS 23.401: "GPRS enhancements for E-UTRAN Access".
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3GPP TS 23.246 version 15.1.0 Release 15 8 ETSI TS 123 246 V15.1.0 (2019-10)
[17] 3GPP TS 36.300: "Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal
Terrestrial Radio Access Network (E-UTRAN)".
[18] 3GPP TS 25.446: "MBMS synchronisation protocol (SYNC)".
[19] IETF RFC 3376: "Internet Group Management Protocol, Version 3".
[20] IETF RFC 3810: "Multicast Listener Discovery Version 2 (MLDv2) for IPv6".
[21] IETF RFC 4607: "Source-Specific Multicast for IP".
[22] IETF RFC 4604: "Using Internet Group Management Protocol Version 3 (IGMPv3) and Multicast
Listener Discovery Protocol Version 2 (MLDv2) for Source specific Multicast".
[23] 3GPP TS 23.203: "Policy and charging control architecture".
[24] 3GPP TS 23.468: "Group Communication System Enablers for LTE (GCSE_LTE)".
[25] 3GPP TS 36.213: "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer
procedures".
[26] 3GPP TS 23.007: "Restoration procedures".
[27] 3GPP TS 29.468: "Group Communication System Enablers for LTE (GCSE_LTE); MB2
reference point; Stage 3".
[28] 3GPP TS 36.444: "M3 Application Protocol (M3AP)".
[29] 3GPP TS 23.682: "Architecture enhancements to facilitate communications with packet data
networks and applications".
[30] 3GPP TS 22.101: "Service aspects; Service principles".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the terms and definitions defined in TR 21.905 [1] and TS 22.146 [2] and the
following apply:
MBMS Service Announcement: Mechanism to allow users to be informed about the MBMS user services available.
MBMS Bearer Service: the service provided by the PS Domain to MBMS User Services to deliver IP multicast
datagrams to multiple receivers using minimum network and radio resources.
MBMS User Service: the MBMS service provided to the end user by means of the MBMS Bearer Service and possibly
other capabilities.
MBMS Service Area: The area within which data of a specific MBMS session are sent. Each individual MBMS
session of an MBMS Bearer Service may be sent to a different MBMS Service Area. This MBMS Service Area is the
same or a subset of the Multicast or Broadcast Service Area as defined in TS 22.146 [2]. An MBMS Service Area
smaller than the Multicast or Broadcast Service Area is typically used for localized services.
MBMS over a Single Frequency Network: See TS 25.346 [10].
Receive Only Mode: A UE configuration option that allows a UE to receive only eMBMS broadcast service without
the need to access and register with the PLMN offering the eMBMS service. A UE configured to operate in Receive
Only Mode receives MBMS service only on a standardised TMGI value range. The UE uses the acquired system
information to receive MBMS broadcast. Use of Receive Only Mode does not require USIM for the UE.
Shared MBMS Network: A network shared by multiple PLMNs that provides MBMS services. The Shared MBMS
network consists of the following shared network elements: BM-SC(s) and MBMS-GW(s). The shared MBMS network
may also include eNB(s), MCE(s), and shared MME(s) for MBMS operation.
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3.2 Abbreviations
For the purposes of the present document, the abbreviations in TR 21.905 [1] and TS 22.146 [2] apply.
EPS Evolved Packet System
C-TEID Common TEID
MBSFN MBMS over a Single Frequency Network
MCE Multi-cell/Multicast Coordination Entity
SSM Source Specific Multicast
TMGI Temporary Mobile Group Identity
TPF Traffic Plane Function
SMN Shared MBMS Network
4 MBMS Architecture
4.1 Overview
MBMS is a point-to-multipoint service in which data is transmitted from a single source entity to multiple recipients.
Transmitting the same data to multiple recipients allows network resources to be shared.
The MBMS bearer service offers two modes:
- Broadcast Mode;
- Multicast Mode.
Broadcast Mode is supported for EPS and GPRS, and Multicast Mode is supported for GPRS. MBMS for EPS supports
E-UTRAN and UTRAN. MBMS for GPRS supports UTRAN and GERAN.
MBMS architecture enables the efficient usage of radio-network and core-network resources, with an emphasis on radio
interface efficiency.
MBMS is realised by the addition of a number of new capabilities to existing functional entities of the 3GPP
architecture and by addition of a number of new functional entities.
The existing PS Domain functional entities (GGSN, SGSN, MME, E-UTRAN, UTRAN, GERAN and UE) are
enhanced to provide the MBMS Bearer Service. In the EPS a functional entity MBMS GW exists at the edge between
the CN and the BM-SC. In the bearer plane, this service provides delivery of IP Multicast datagrams from the Gi and
SGi-mb reference points to UEs with a specified Quality of Service. In the control plane, this service provides
mechanisms for:
- managing the MBMS bearer service activation status of UEs (in the case of multicast mode);
- outsourcing authorisation decisions to the MBMS User Service (i.e. to the BM-SC) (in the case of multicast
mode);
- providing control of session initiation/modification/termination by the MBMS User Service and managing bearer
resources for the distribution of MBMS data (in the case or multicast and broadcast modes).
A particular instance of the MBMS Bearer Service is identified by an IP Multicast Address and an APN Network
Identifier. A TMGI also can be used to identify one MBMS Bearer Service inside one PLMN.
For GPRS the boundary of the MBMS Bearer Service is the Gmb and Gi reference points as shown in Figure 1 below.
The former provides access to the control plane functions and the latter the bearer plane. For EPS the boundary is the
SGmb and the SGi-mb as shown in figure 1b below.
A functional entity, the Broadcast Multicast Service Centre (BM-SC) provides a set of functions for MBMS User
Services. BM-SC functions for different MBMS User Services may be supported from the same or different physical
network elements.
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4.2 Reference Architecture Model
4.2.1 GPRS
PDN
( e . g )
. Internet
Content
Provider /
Multicast
Broadcast
Source
HLR
Gr
Content
Gmb
Uu Provider /
Iu Gn /Gp
Multicast
GGSN
UE UTRAN SGSN
BM - SC
Broadcast
TPF
Iu Source
Gi
Mz
Gi
.
Iu /Gb
Gmc
BM-SC
Um
Iu
UE GERAN Other PLMN
Note 1: Network entities and reference points solely used by the MBMS user service (e.g. for service
announcement as described in clause 4.4.1.2) are not shown in this figure.
Note 2: Gp applies only when SGSN and GGSN are in different PLMNs.
Note 3: the Iu/Gn reference point above is a direct tunnel according to clause 5.6.2.2, figure 6b in TS 23.060 [15]
with IP multicast based addressing according to RFC 4607 [21].

Figure 1a: Reference architecture for GPRS to support the MBMS bearer service with GERAN and
UTRAN
4.2.2 EPS
PDN
Gateway
MME
M3
SGi
E-UTRAN Uu
Sm
SGmb
UE
MBMS Bearer
E-UTRAN
MBMS
Service
GW
M1 SGi-mb
Content
MBMS User
Service Provider
Iu Sn
Uu
UTRAN SGSN
UE
BM-SC
Figure 1b: Reference architecture for Evolved Packet System with E-UTRAN and UTRAN (MBMS
Broadcast Mode only)
NOTE 1: In addition to MBMS Bearers (over SGmb/SGi-mb), the BM-SC may use EPS Bearers (over SGi) to
realize an MBMS User Service as specified in TS 26.346 [7].
NOTE 2: The MCE (see TS 36.300 [17]) is not shown in the figure.
NOTE 3: MBMS service over Gn-SGSN is supported when the MBMS-GW is co-located with the PDN GW and
this PDN GW has the necessary GGSN functions to control the MBMS Bearer Service over Gn.
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4.3 MBMS Specific Reference points
4.3.1 Gmb
Signalling between GGSN and BM-SC is exchanged at Gmb reference point. This represents the network side boundary
of the MBMS Bearer Service from a control plane perspective. This includes user specific Gmb signalling and MBMS
bearer service specific signalling.
MBMS bearer service specific Gmb signalling:
- The GGSN establishes the MBMS bearer context and registers at BM-SC.
- The GGSN or the BM-SC releases the MBMS bearer context and de-registers the GGSN from the BM-SC.
- The BM-SC indicates session start, update and stop to the GGSN including session attributes like QoS and
MBMS service area.
User specific Gmb signalling:
- The BM-SC authorises the user specific MBMS multicast service activation (join) at the GGSN.
- The GGSN reports to the BM-SC the successful user specific MBMS multicast activation (join) to allow the
BM-SC to synchronise the BM-SC MBMS UE context with the MBMS UE contexts in the SGSN and GGSN.
- The GGSN reports to the BM-SC when a user specific MBMS multicast service is released or deactivated (e.g.
at implicit detach). The GGSN makes this report in order to synchronise the BM-SC MBMS UE context with the
MBMS UE contexts in the SGSN and GGSN.
The BM-SC initiates the deactivation of a user specific MBMS bearer service when the MBMS user service is
terminated.
BM-SC functions for different MBMS bearer services may be provided by different physical network elements. Further,
MBMS bearer service specific and user specific signalling for the same MBMS bearer service may also be provided by
different physical network elements. To allow this distribution of BM-SC functions, the Gmb protocol must support the
use of proxies to correctly route the different signalling interactions in a manner which is transparent to the GGSN.
4.3.1a SGmb
The SGmb reference point has similar functions with the Gmb interface in control plane except for the Multicast Mode
related functions. Specifically,
MBMS bearer service specific SGmb signalling:
- The BM-SC indicates session start, update and stop to the MBMS-GW including session attributes like QoS and
MBMS service area, and some of attributes may be different from them in Gmb.
4.3.2 Mz
Mz is the roaming variant of the Gmb reference point with the same functionality as described under Gmb, i.e. with
MBMS bearer and User specific signalling.
MBMS bearer and User specific Mz signalling is used between a BM-SC in the visited PLMN and a BM-SC in the
home PLMN when MBMS services from the home PLMN are offered by the visited PLMN.
User specific signalling is used between a BM-SC in the visited PLMN and a BM-SC in the home PLMN when the
visited PLMN offers MBMS user services to roaming users. This user specific Mz signalling provides home PLMN
authorisation for MBMS user services that are provided by the visited PLMN. This mechanism supports only MBMS
user service classes that are offered by the visited and by the home PLMN.
Mz may use proxying capabilities as described for Gmb, e.g. to proxy signalling between BM-SCs. An APN may be
included in the signalling between BM-SCs, which is used to select an appropriate GGSN to access the MBMS service
aiming for an optimized routing, resource saving, or operator policy.
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NOTE: For EPS, the Mz reference point is not supported in this release.
4.3.3 Reference Points for Evolved Packet System
NOTE: The below listed reference points are applicable for the E-UTRAN and UTRAN MBMS Broadcast Mode
(with or without counting) only.
M1: It is the
...