The MBMS‑GW is a logical entity that is present between the BM‑SC and eNBs whose principal functions is the sending/broadcasting of MBMS packets to each eNB transmitting the service.
The MBMS‑GW uses IP Multicast as the means of forwarding MBMS
user data to the eNB. The MBMS GW performs MBMS Session Control Signalling (Session start/update/stop) towards
the E‑UTRAN via MME.
The MMS Relay/Server is responsible for storage and notification, reports, and general handling of messages. The
MMS Relay/Server may also provide convergence functionality between External Servers and MMS User Agents and
thus enable the integration of different server types across different networks.
The MRB supports the sharing of a pool of heterogeneous MRF resources by multiple heterogeneous applications.
MRB assigns (and later releases) specific suitable MRF resources to calls as requested by the consuming applications, based on MRF attributes specified by the applications as well as other criteria.
The MRB may take the following kinds of information into account when assigning MRF resources to an application:
the specific characteristics of the media resources required for the call or calls;
the identity of the application;
rules for allocating MRF resources across different applications;
per-application or per-subscriber SLA or QoS criteria; and
The MS consists of the physical equipment used by a PLMN subscriber; it comprises the Mobile Equipment
(ME) and the Subscriber Identity Module (SIM), called UMTS Subscriber Identity Module (USIM) for Release 99 and
following. The ME comprises the Mobile Termination (MT) which, depending on the application and services, may
support various combinations of Terminal Adapter (TA) and Terminal Equipment (TE) functional groups. These
functional groups are described in TS 24.002.
The Mobile-services Switching Centre (MSC) constitutes the interface between the radio system and the fixed
networks. The MSC performs all necessary functions in order to handle the circuit switched services to and from the
When needed, the MSC can be implemented in two different entities: the MSC-S, handling only signalling, and the
CS-MGW, handling user's data. A MSC Server and a CS-MGW make up the full functionality of a MSC.
The MSC server mainly comprises the call control and mobility control parts of a GSM/UMTS MSC. It is also integrated with a VLR to hold the mobile subscriber's service data and CAMEL related
The MSC server terminates the user-network signalling and translates it into the signalling
over the Nc interface. The MSC Server terminates the Iu control plane signalling and its transport bearer. It also terminates the signalling over the Mc interface with the Media Gateway.
The MSCF is a functional entity which may be connected to the MMS Relay/Server to execute messaging related
service logic. It may influence addressing, routeing and charging for multimedia messages. Furthermore it may control
access rights of the user.
To support translation of the IMSI to External Identifier(s) at the network egress, an AAA function (MTC AAA) is used
in the HPLMN. The MTC AAA may be deployed to return the External Identifier(s) based on IMSI. Alternatively the
MTC AAA may be deployed as a RADIUS/Diameter proxy between the GGSN/PGW and the AAA server in the
To support the Indirect and Hybrid models of MTC, one or more instances of an MTC InterWorking Function (MTC-IWF) reside in the HPLMN. A MTC-IWF may be a standalone entity or a functional entity of another network element.
The MTC-IWF hides the internal PLMN topology and relays or translates signaling protocols used over Tsp to invoke
specific functionality in the PLMN.