MBMS OV - (4) Architecture in MBMS and E-MBMS

1.1. MBMS Architecture in 3G Overview

The MBMS Bearer Service Architecture is defined in 3GPP TS 23.246. The MBMS User Service interfaces to the MBMS system via 3 entities.

- The BM-SC.

- The GGSN.

- The UE.

- 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.

- The BM-SC provides functions for MBMS user service provisioning and delivery to the content provider. It can also serve as an entry point for IP MBMS data traffic from the MBMS User Service source.

- The GGSN serves as an entry point for IP multicast traffic as MBMS data from the BM-SC

Figure: MBMS bearer service architecture

http://docs.google.com/View?id=ddh56dhg_101fbbwv2fx

http://docs.google.com/View?id=ddh56dhg_103cfrv5jjk

The existing PS Domain functional entities (GGSN, SGSN, UTRAN, GERAN and UE) are enhanced to provide the MBMS Bearer Service.

1.2. E-MBMS Architecture in LTE EPS Overview

Figure: E-MBMS bearer service architecture

http://docs.google.com/View?id=ddh56dhg_105grx6vmc6

MBMS Data Sources and Content Provider to BM-SC

- The reference point from the content provider to the BM-SC is not standardised by 3GPP in this release of the specification

1.3. E-MBMS deployment scenarios in LTE

In terms of deployment scenarios of MBMS in E-UTRAN, the following alternatives can be listed:

- Carrier type: dedicated vs. mixed carrier;

- MBSFN transmission: multi-cell vs. single-cell transmission;

- Radio bearer type: p-t-m vs. p-t-p;

- Counting: yes or no;

- Audience measurement: yes or no;

- ON/OFF control of MBMS service delivery: yes or no;

- PTP / PTM radio bearer switching: yes or no

Table below lists the combinations of the above alternatives that are specifically supported in E-UTRAN:

Scenario	Carrier	Transmission	Radio Bearer Type	Counting	remark
1	Dedicated	Multi-cell	p-t-m	No	From 1 to n cells; Audience Measurement (FFS)
2	Mixed	Multi-cell	p-t-m	No	Audience Measurement (FFS)
3	Mixed	Single-cell	p-t-m	Yes