IEC 62056-53:2006

INTERNATIONAL IEC
STANDARD 62056-53
Second edition
2006-12
Electricity metering –
Data exchange for meter reading,
tariff and load control –
Part 53:
COSEM application layer
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INTERNATIONAL IEC
STANDARD 62056-53
Second edition
2006-12
Electricity metering –
Data exchange for meter reading,
tariff and load control –
Part 53:
COSEM application layer
© IEC 2006 ⎯ Copyright - all rights reserved
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For price, see current catalogue

– 2 – 62056-53 © IEC:2006(E)
CONTENTS
FOREWORD.5

1 Scope.7
2 Normative references .7
3 Terms, definitions and abbreviations .8
4 The COSEM communications framework .10
4.1 Client/server type operation, communication profiles .10
4.2 Connection (association) oriented operation.12
5 Overview: the COSEM application layer .12
5.1 Specification method .12
5.2 Application layer structure .12
5.3 Service specification .13
5.4 Layer management services.15
5.5 Protocol specification .15
6 COSEM application layer – Service specification.16
6.1 Summary of services .16
6.2 Application association establishment and release .16
6.3 Special application associations .17
6.4 Data communication.18
6.5 Client COSEM application layer services.19
6.6 Server COSEM application layer services.38
6.7 Summary of COSEM application layer services and service parameters .55
7 COSEM application layer protocol specification .59
7.1 State definitions for the client side control function.59
7.2 State definitions for the server side control function .61
7.3 Protocol for application association establishment/release .62
7.4 Protocol for data communications.74
8 Specification of COSEM data types .89
8.1 The COSEM APDUs.89
8.2 The ACSE APDUs .90
8.3 Useful types .93
8.4 The xDLMS-Initiate.request/response/ConfirmedServiceError PDUs.98
8.5 The conformance block .98
8.6 Definition of APDUs for data communication .99

Annex A (normative) The xDLMS application service element.105
Annex B (normative) Using the COSEM Application Layer in various communication
profiles .107
Annex C (informative) AARQ and AARE encoding examples.126
Annex D (informative) Data model and protocol .138

Bibliography.139

INDEX .142

62056-53 © IEC:2006(E) – 3 –
Figure 1 – Client/server relationship in COSEM .10
Figure 2 – Exchanging messages via the communication protocol .11
Figure 3 – The COSEM application layer on the top of various lower layer stacks.11
Figure 4 – A complete communication session in the CO environment .12
Figure 5 – The structure of the COSEM application layers .13
Figure 6 – Structure of the COSEM AL when the server is using SN references.15
Figure 7 – Summary of COSEM application layer services .16
Figure 8 – Normal service sequence for the COSEM-OPEN service.17
Figure 9 – Client side services for application association establishment .19
Figure 10 – Client side services for releasing an application association.23
Figure 11 – Client side data communication services .26
Figure 12 – Client side services for event notification .35
Figure 13 – Server side services for application association establishment .38
Figure 14 – Server side services for releasing an application association .40
Figure 15 – Server side data communications services using LN referencing.44
Figure 16 – Partial state machine for the client side control function .60
Figure 17 – Partial state machine for the server side control function.61
Figure 18 – MSC for successful application association establishment preceded by a
successful lower layer connection establishment .63
Figure 19 – Graceful association release using the A-RELEASE service.69
Figure 20 – Graceful release of an application association by disconnection the
supporting layer .70
Figure 21 – Aborting an application association following a PH-ABORT.indication .71
Figure 22 – MSC for a confirmed GET service in case of success.75
Figure 23 – MSC for a confirmed SET service in case of success .75
Figure 24 – MSC for the SET service in case of failure .76
Figure 25 – MSC for the ACTION service (simplest case) .76
Figure 26 – Long data with the GET service in three data blocks .81
Figure 27 – Long data transfer in three data blocks with the SET service.83
Figure 28 – Long data transfer with the ACTION service.85
Figure 29 – MSC for the ReadRequest/Response services .87
Figure B.1 – Identification/addressing scheme in the 3-layer, connection-oriented,
HDLC based communication profile .110
Figure B.2 – Data link layer services provided to and used by the client COSEM
application layer .111
Figure B.3 – Data link layer services provided to and used by the server COSEM
application layer .112
Figure B.4 – Example: EventNotificaton triggered by the client .115
Figure B.5 – Multi-drop configuration and its model .116
Figure B.6 – Master/ Slave operation on the multi-drop bus .116
Figure B.7 – COSEM as a standard Internet application protocol .118
Figure B.8 – Examples for lower-layer protocols in the TCP-UDP/IP based profiles .119
Figure B.9 – Identification/addressing scheme in the TCP-UDP/IP based profile(s).120
Figure B.10 – Summary of TCP/UDP layer services on the client and server side .121
Figure D.1 – The three-step approach of COSEM .138

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Table 1 – Mapping between client side LN and server side SN referencing services .37
Table 2 – Application layer services – summary.55
Table 3 – Summary of the service parameters in the COSEM-OPEN service primitives.56
Table 4 – Summary of the service parameters in the COSEM-RELEASE service primitives .57
Table 5 – Summary of the service parameters in the COSEM-ABORT service primitives .57
Table 6 – Summary of the service parameters in the COSEM GET service primitives .57
Table 7 – Summary of the service parameters in the COSEM SET service primitives.58
Table 8 – Summary of the service parameters in the COSEM ACTION service primitives .58
Table 9 – Summary of the service parameters in the COSEM EventNotification service
primitives .59
Table 10 – Mapping between the EventNotification and InformationReport services.88
Table B.1 – Application associations and data exchange in the 3-layer, connection-
oriented, HDLC based profile.113
Table B.2 –Application associations and data exchange in the TCP-UDP/IP based profile .123

62056-53 © IEC:2006(E) – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICITY METERING –
DATA EXCHANGE FOR METER READING,
TARIFF AND LOAD CONTROL –
Part 53: COSEM application layer

FOREWORD
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