IEC TR 62541-1:2016

IEC TR 62541-1 ®
Edition 2.0 2016-10
TECHNICAL
REPORT
colour
inside
OPC unified architecture –
Part 1: Overview and concepts
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IEC TR 62541-1 ®
Edition 2.0 2016-10
TECHNICAL
REPORT
colour
inside
OPC unified architecture –
Part 1: Overview and concepts
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.100.01 ISBN 978-2-8322-3640-6

– 2 – IEC TR 62541-1:2016 © IEC 2016
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references. 6
3 Terms, definitions and abbreviations . 6
3.1 Terms and definitions . 6
3.2 Abbreviations . 10
4 Structure of the OPC UA series . 10
4.1 Specification organization. 10
4.2 Core specification parts . 11
4.3 Access Type specification parts . 12
4.4 Utility specification parts. 12
5 IEC 62541 standards – Overview . 13
5.1 UA scope . 13
5.2 General . 13
5.3 Design goals . 13
5.4 Integrated models and services . 15
5.4.1 Security model . 15
5.4.2 Integrated AddressSpace model . 16
5.4.3 Integrated object model . 16
5.4.4 Integrated services . 17
5.5 Sessions . 17
5.6 Redundancy . 17
6 Systems concepts . 17
6.1 Overview. 17
6.2 OPC UA Clients . 18
6.3 OPC UA Servers . 19
6.3.1 General . 19
6.3.2 Real objects . 19
6.3.3 OPC UA Server application . 19
6.3.4 OPC UA AddressSpace . 20
6.3.5 Publisher/subscriber entities . 20
6.3.6 OPC UA Service Interface . 20
6.3.7 Server to Server interactions . 21
7 Service Sets . 22
7.1 General . 22
7.2 Discovery Service Set . 22
7.3 SecureChannel Service Set . 22
7.4 Session Service Set . 23
7.5 NodeManagement Service Set . 23
7.6 View Service Set . 24
7.7 Query Service Set . 24
7.8 Attribute Service Set . 24
7.9 Method Service Set . 24
7.10 MonitoredItem Service Set . 24
7.11 Subscription Service Set . 25
Bibliography . 26

Figure 1 – OPC UA Specification organization . 11
Figure 2 – OPC UA Target applications . 14
Figure 3 – OPC UA System architecture . 18
Figure 4 – OPC UA Client architecture . 18
Figure 5 – OPC UA Server architecture . 19
Figure 6 – Peer-to-peer interactions between Servers . 21
Figure 7 – Chained Server example . 22
Figure 8 – SecureChannel and Session Services . 23

– 4 – IEC TR 62541-1:2016 © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPC UNIFIED ARCHITECTURE –
Part 1: Overview and concepts
FOREWORD
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example "state of the art".
IEC TR 62541-1, which is a technical report, has been prepared by subcommittee 65E:
Devices and integration in enterprise systems, of IEC technical committee 65: Industrial-
process measurement, control and automation.
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
65E/414/DTR 65E/463/RVC
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.

This second edition cancels and replaces the first edition of IEC TR 62541-1, published in
2010.
This edition includes no technical changes with respect to the previous edition but includes
updates to reflect changes or additions in normative parts of IEC 62541.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
Throughout this document and the referenced othe
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