CLC IEC/TR 62541-1:2021

OPC unified architecture - Part 1: Overview and concepts

This part of IEC 62541 presents the concepts and overview of the OPC Unified Architecture (OPC UA). Reading this document is helpful to understand the remaining parts of this multi-part document set. Each of the other parts of IEC 62451 is briefly explained along with a suggested reading order.

OPC Unified Architecture - Teil 1: Übersicht und Konzepte

Architecture unifiée OPC - Partie 1: Vue d'ensemble et concepts

IEC TR 62541-1:2020 est disponible sous forme de IEC TR 62541-1:2020 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.

Enotna arhitektura OPC - 1. del: Pregled in koncepti

General Information

• Status: Published
• Publication Date: 15-Jul-2021
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.100.01 - Open systems interconnection in general
• Technical Committee: CLC/TC 65X - Industrial-process measurement, control and automation
• Drafting Committee: CLC/TC 65X - Industrial-process measurement, control and automation
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 16-Jul-2021
• Due Date: 02-Sep-2022
• Completion Date: 16-Jul-2021
• Ref Project: SIST-TP CLC IEC/TR 62541-1:2021 - OPC unified architecture - Part 1: Overview and concepts

Relations

• Replaces: CLC/TR 62541-1:2010 - OPC unified architecture - Part 1: Overview and concepts
• Effective Date: 15-Dec-2020

Standards Content (Sample)

SLOVENSKI STANDARD
01-oktober-2021
Nadomešča:
SIST-TP CLC/TR 62541-1:2010
Enotna arhitektura OPC - 1. del: Pregled in koncepti
OPC unified architecture - Part 1: Overview and concepts
OPC Unified Architecture - Teil 1: Übersicht und Konzepte
Architecture unifiée OPC - Partie 1: Vue d'ensemble et concepts
Ta slovenski standard je istoveten z: CLC IEC/TR 62541-1:2021
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
35.100.01 Medsebojno povezovanje Open systems
odprtih sistemov na splošno interconnection in general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

TECHNICAL REPORT CLC IEC/TR 62541-1

RAPPORT TECHNIQUE
TECHNISCHER BERICHT
July 2021
ICS 25.040.40; 35.100.01 Supersedes CLC/TR 62541-1:2010
English Version
OPC unified architecture - Part 1: Overview and concepts
(IEC/TR 62541-1:2020)
Architecture unifiée OPC - Partie 1: Vue d'ensemble et OPC Unified Architecture - Teil 1: Übersicht und Konzepte
concepts (IEC/TR 62541-1:2020)
(IEC/TR 62541-1:2020)
This Technical Report was approved by CENELEC on 2021-07-05.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. CLC IEC/TR 62541-1:2021 E

European foreword
This document (CLC IEC/TR 62541-1:2021) consists of the text of IEC/TR 62541-1:2020, prepared by
SC 65E "Devices and integration in enterprise systems" of IEC/TC 65 "Industrial-process
measurement, control and automation".
This document supersedes CLC/TR 62541-1:2010.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Technical Report IEC/TR 62541-1:2020 was approved by CENELEC as a
European Technical Report without any modification.
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cenelec.eu.
Publication Year Title EN/HD Year
IEC/TR 62541-2 - OPC unified architecture – Part 2: CLC/TR 62541-2 -
Security Mode
IEC 62541-3 - OPC Unified Architecture - Part 3: EN IEC 62541-3 -
Address Space Model
IEC 62541-4 - OPC Unified Architecture - Part 4: EN IEC 62541-4 -
Services
IEC 62541-5 - OPC Unified Architecture - Part 5: EN IEC 62541-5 -
Information Model
IEC 62541-6 - OPC Unified Architecture - Part 6: EN IEC 62541-6 -
Mappings
IEC 62541-7 - OPC unified architecture - Part 7: Profiles EN IEC 62541-7 -
IEC 62541-8 - OPC Unified Architecture - Part 8: Data EN IEC 62541-8 -
Access
IEC 62541-9 - OPC Unified Architecture - Part 9: Alarms EN IEC 62541-9 -
and Conditions
IEC 62541-10 - OPC Unified Architecture - Part 10: EN IEC 62541-10 -
Programs
IEC 62541-11 - OPC Unified Architecture - Part 11: EN IEC 62541-11 -
Historical Access
IEC 62541-12 - OPC unified architecture - Part 12: EN IEC 62541-12 -
Discovery and global services
IEC 62541-13 - OPC Unified Architecture - Part 13: EN IEC 62541-13 -
Aggregates
IEC 62541-14 - OPC unified architecture - Part 14: EN IEC 62541-14 -
PubSub
ITU X.509 - Information technology – Open Systems
Interconnection – The Directory: Public-
key and attribute certificate
frameworkshttps://www.itu.int/rec/T-REC-
X.509
IEC TR 62541-1 ®
Edition 3.0 2020-11
TECHNICAL
REPORT
colour
inside
OPC unified architecture –
Part 1: Overview and concepts
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.100.01 ISBN 978-2-8322-9076-7

– 2 – IEC TR 62541-1:2020 © IEC 2020
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms, definitions, and abbreviated terms . 7
3.1 Terms and definitions . 7
3.2 Abbreviated terms . 11
4 Structure of the OPC UA series . 12
4.1 Specification organization . 12
4.2 Core specification parts . 12
4.3 Access Type specification parts . 13
4.4 Utility specification parts . 13
5 Overview . 14
5.1 UA scope . 14
5.2 General . 14
5.3 Design goals . 14
5.4 Integrated models and services. 16
5.4.1 Security model . 16
5.4.2 Integrated AddressSpace model . 17
5.4.3 Integrated object model . 18
5.4.4 Integrated services . 18
5.5 Sessions . 18
6 Systems concepts . 19
6.1 Client Server Overview . 19
6.2 OPC UA Clients . 19
6.3 OPC UA Servers . 20
6.3.1 General . 20
6.3.2 Real objects . 20
6.3.3 Server application . 20
6.3.4 OPC UA AddressSpace . 21
6.3.5 Subscription entities . 21
6.3.6 OPC UA Service Interface . 21
6.3.7 Server to Server interactions . 22
6.4 Redundancy . 23
6.5 Publish-Subscribe . 23
6.6 Synergy of models . 24
7 Service Sets . 25
7.1 General . 25
7.2 Discovery Service Set . 25
7.3 SecureChannel Service Set . 25
7.4 Session Service Set . 26
7.5 NodeManagement Service Set . 26
7.6 View Service Set . 26
7.7 Query Service Set . 26
7.8 Attribute Service Set . 27
7.9 Method Service Set . 27
7.10 MonitoredItem Service Set . 27

IEC TR 62541-1:2020 © IEC 2020 – 3 –
7.11 Subscription Service Set . 28

Figure 1 – OPC UA specification organization . 12
Figure 2 – OPC UA target applications . 15
Figure 3 – OPC UA System architecture . 19
Figure 4 – OPC UA Client architecture . 19
Figure 5 – OPC UA Server architecture . 20
Figure 6 – Peer-to-peer interactions between Servers . 22
Figure 7 – Chained Server example . 23
Figure 8 – Integrated Client Server and PubSub models . 24
Figure 9 – SecureChannel and Session Services . 26

– 4 – IEC TR 62541-1:2020 © IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPC UNIFIED ARCHITECTURE –
Part 1: Overview and concepts
FOREWORD
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