8 Protocol structure for MBMS related interface in E-UTRAN

36.4403GPPEvolved Universal Terrestrial Radio Access Network (E-UTRAN)General aspects and principles for interfaces supporting Multimedia Broadcast Multicast Service (MBMS) within E-UTRANRelease 17TS

8.1 General

MBMS related E-UTRAN interfaces, M1, M2 and M3, are layered into a Radio Network Layer (RNL) and a Transport Network Layer (TNL).

The radio network signalling over M3 consists of the M3 Application Protocol (M3AP). The M3AP protocol (TS 36.444 [5]) consists of procedures between the EPC and E-UTRAN for MBMS.

The radio network signalling over M2 consists of the M2 Application Protocol (M2AP). The M2AP protocol (TS 36.443 [4]) consists of procedures between the MCE and eNB for MBMS.

8.2 M1

The protocol stack structure for M1 interface is defined in TS 36.445 section 5.1 [6].

MBMS user data is distributed from the MBMS GW to eNBs by using IP multicast through the M1 interface. An eNB joins the IP multicast address allocated by MBMS GW during the MBMS Session Start procedure (TS 23.246 [8]).

8.3 M2

The protocol stack structure for M2 interface is defined in TS 36.442 section 4.1.1 [3].

8.4 M3

The protocol stack structure for M3 interface is defined in TS 36.442 section 5.1.1 [3].