Content for TR 43.868 Word version: 12.1.0

3.1 Definitions 3.2 Symbols 3.3 Abbreviations 4.1 General 4.2 Overload control
...

0 Introduction p. 4

The present document captures the results of the feasibility study for GERAN improvements for Machine-type Communications.

1 Scope p. 5

The present document contains the results from the study of improvements for Machine-type Communications in GERAN.

The following items are in the scope of the study:

GERAN enhancements for Smart metering
Enhancements which enable or improve efficient use of RAN resources and/or which lower complexity when a large number of MTC devices are served.
GERAN enhancements for overload and congestion control on the radio, A and Gb interface
GERAN enhancements regarding identifiers used for MTC devices in the radio access network

2 References p. 5

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]

TR 21.905: "Vocabulary for 3GPP Specifications".

[2]

TS 22.368: "Service requirements for Machine-Type Communications (MTC); Stage 1".

[3]

SP-100224: "Liaison Statement: Prioritization of NIMTC functions in Rel-10".

[4]

TS 44.018: "Mobile radio interface layer 3 specification; Radio Resource Control (RRC) protocol".

[5]

TS 45.005: "Radio transmission and reception".

[6]

TR 25.942: "Radio Frequency (RF) system scenarios".

3 Definitions, symbols and abbreviations p. 5

3.1 Definitions p. 5

For the purposes of the present document, the terms and definitions given in TR 21.905 and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905.

MTC Device:

A MTC Device is a UE equipped for Machine Type Communication, which communicates through a PLMN with MTC Server(s) and/or other MTC Device(s).

MTC Feature:

MTC Features are network functions to optimise the network for use by M2M applications.

3.2 Symbols p. 6

Void.

3.3 Abbreviations p. 6

For the purposes of the present document, the abbreviations given in TR 21.905 and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905.)

CCCH

Common Control Channel

GERANIMTC

GERAN Improvements for Machine Type Communications

Internet Protocol

KPI

Key Performance Indicator

Mobile Station

MTC

Machine Type Communications

PDCH

Packet Data Channel

4 Areas for study to effectively support MTC in GERAN p. 6

4.1 General p. 6

Subclause 4 contains the outcome of the study of GERAN enhancements driven by the prioritized general MTC functions as defined in [3] that are considered applicable to GERAN specifications.

4.2 Overload control p. 6

4.2.1 General p. 6

Overload Control refers to use cases Radio Network Congestion, Signalling Network and Core Network Congestion as described in [2] Annex A.

4.2.2 Description and Analysis p. 6

4.2.2.1 CCCH Overload Control p. 6

4.2.2.1.1 Description and Analysis p. 6

The large amount of access attempts that can be generated from mobile stations used for MTC is believed to increase the load and cause congestion on the common control channel (CCCH) and therefore may negatively impact legacy services.

The legacy pre-release 10 RR connection establishment procedure is not sufficient for the network to avoid CCCH congestion that can be caused by mobile stations used for MTC. However the implicit reject procedure specified in release 10 in TS 44.018 can effectively protect the legacy services from CCCH congestion that can be caused by mobile stations configured with low access priority.

4.2.2.1.2 Result p. 6

By using the implicit reject procedure, the network can effectively protect the CCCH from being overloaded by mobile stations configured with low access priority.

The objective of CCCH overload control in MTC study has been met with the implicit reject procedure with respect to preventing overload of CCCH hence minimising impact to legacy services from devices configured for low access priority.