IEC 61784-2-0:2023

Industrial networks - Profiles - Part 2-0: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 - General concepts and terminology

IEC 61784-2-0:2023 specifies:
basic principles of performance indicators expressing RTE performance of a CP (see 5.1);
how an application-dependent class could be used to find out a suitable CP to meet application requirements (see 5.2);
characteristics of RTE performance indicators (see 5.3);
the methodology of a conformance test for an RTE end device for one or more CPs (see Clause 6).

Réseaux industriels - Profils - Partie 2-0: Profils de bus de terrain supplémentaires pour les réseaux en temps réel fondés sur l’ISO/IEC/IEEE 8802-3 - Concepts généraux et terminologie

L'IEC 61784-2-0:2023 spécifie:
les principes de base des indicateurs de performance exprimant la performance RTE d’un CP (voir 5.1);
la façon dont une classe dépendante de l’application peut être utilisée pour rechercher un CP adapté aux exigences d’une application (voir 5.2);
les caractéristiques des indicateurs de performance RTE (voir 5.3);
la méthodologie d’un essai de conformité d’un élément final RTE pour un ou plusieurs CP (voir l’Article 6).

General Information

• Status: Published
• Publication Date: 21-Mar-2023
• ICS: 35.100.20 - Data link layer
• ICS: 35.240.50 - IT applications in industry
• Technical Committee: SC 65C - Industrial networks
• Drafting Committee: WG 9 - TC 65/SC 65C/WG 9
• Current Stage: PPUB - Publication issued
• Start Date: 31-Mar-2023
• Completion Date: 22-Mar-2023

Relations

• Replaces: IEC 61784-2:2019 - Industrial communication networks - Profiles - Part 2: Additional fieldbus profiles for real-time networks based on ISO/IEC/IEEE 8802-3
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61784-2-0
®

Edition 1.0 2023-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Industrial networks – Profiles –
Part 2-0: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 –
General concepts and terminology

Réseaux industriels – Profils –
Partie 2-0: Profils de bus de terrain supplémentaires pour les réseaux en temps
réel fondés sur l’ISO/IEC/IEEE 8802-3 – Concepts généraux et terminologie

IEC 61784-2-0:2023-03(en-fr)

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IEC 61784-2-0

®


Edition 1.0 2023-03




INTERNATIONAL



STANDARD




NORME


INTERNATIONALE
colour

inside










Industrial networks – Profiles –

Part 2-0: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 –

General concepts and terminology



Réseaux industriels – Profils –

Partie 2-0: Profils de bus de terrain supplémentaires pour les réseaux en temps


réel fondés sur l’ISO/IEC/IEEE 8802-3 – Concepts généraux et terminologie













INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 35.100.20; 35.240.50 ISBN 978-2-8322-6622-9




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® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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– 2 – IEC 61784-2-0:2023 © IEC 2023
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions, abbreviated terms, acronyms, and conventions . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms and acronyms . 10
3.3 Common symbols . 11
3.4 Conventions . 11
3.4.1 Conventions common to all layers . 11
3.4.2 Physical layer . 13
3.4.3 Data-link layer . 13
3.4.4 Application layer . 14
4 Conformance to communication profiles . 14
5 RTE performance indicators . 15
5.1 Basic principles of performance indicators . 15
5.2 Application requirements . 16
5.3 Performance indicators . 16
5.3.1 Delivery time . 16
5.3.2 Number of RTE end-stations . 17
5.3.3 Basic network topology . 17
5.3.4 Number of switches between RTE end-stations . 17
5.3.5 Throughput RTE . 17
5.3.6 Non-RTE bandwidth . 17
5.3.7 Time synchronization accuracy . 17
5.3.8 Non-time-based synchronization accuracy . 18
5.3.9 Redundancy recovery time . 18
6 Conformance tests . 18
6.1 Concept . 18
6.2 Methodology . 19
6.3 Test conditions and test cases . 19
6.4 Test procedure and measuring . 19
6.5 Test report . 20
Bibliography . 21

Figure 1 – Example of graphical representation of consistent indicators . 16
Figure 2 – Conformance test overview . 18

Table 1 – Layout of profile (sub)clause selection tables . 12
Table 2 – Contents of (sub)clause selection tables . 12
Table 3 – Layout of service selection tables . 12
Table 4 – Contents of service selection tables . 13

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IEC 61784-2-0:2023 © IEC 2023 – 3 –
Table 5 – Layout of parameter selection tables . 13
Table 6 – Contents of parameter selection tables. 13
Table 7 – Layout of class attribute selection tables . 14
Table 8 – Contents of class attribute selection tables . 14
Table 9 – Basic network topology types . 17

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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

INDUSTRIAL NETWORKS –
PROFILES –

Part 2-0: Additional real-time fieldbus profiles
based on ISO/IEC/IEEE 8802-3 –
General concepts and terminology

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
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preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
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Attention is drawn to the fact that the use of some of the associated protocol types is restricted
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be used with other layer protocols of the same type, or in other type combinations explicitly
authorized by their respective intellectual property right holders.
NOTE Combinations of protocol types are specified in the IEC 61784-1 series and the IEC 61784-2 series.
IEC 61784-2-0 has been prepared by subcommittee 65C: Industrial networks, of IEC technical
committee 65: Industrial-process measurement, control and automation. It is an International
Standard.
This first edition, together with the other parts of the same series, cancels and replaces the
fourth edition of IEC 61784-2 published in 2019. This first edition constitutes a technical revision.

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IEC 61784-2-0:2023 © IEC 2023 – 5 –
This edition includes the following significant technical changes with respect to
IEC 61784-2:2019:
a) split of the original IEC 61784-2 into several subparts, one subpart for the material of a
generic nature, and one subpart for each Communication Profile Family specified in the
original document.
The text of this International Standard is based on the following documents:
Draft Report on voting
65C/1209/FDIS 65C/1237/RVD

Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts of the IEC 61784-2 series, published under the general title
Industrial networks – Profiles – Part 2: Additional real-time fieldbus profiles based on
ISO/IEC/IEEE 8802-3, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The "colour inside" logo on the cover page of this document indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

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– 6 – IEC 61784-2-0:2023 © IEC 2023
INTRODUCTION
The IEC 61784-2 series provides additional Communication Profiles (CP) to the existing
Communication Profile Families (CPF) of the IEC 61784-1 series and additional CPFs with one
or more CPs. These profiles meet the industrial automation market objective of identifying Real-
Time Ethernet (RTE) communication networks coexisting with ISO/IEC/IEEE 8802-3 –
commonly known as Ethernet. These RTE communication networks use provisions of
ISO/IEC/IEEE 8802-3 for the lower communication stack layers and additionally provide more
predictable and reliable real-time data transfer and means for support of precise
synchronization of automation equipment.
More specifically, these profiles help to correctly state the compliance of RTE communication
networks with ISO/IEC/IEEE 8802-3, and to avoid the spreading of divergent implementations.
Adoption of Ethernet technology for industrial communication between controllers and even for
communication with field devices promotes the use of Internet technologies in the field area.
This availability would be unacceptable if it causes the loss of features required in the field area
for industrial communication automation networks, such as:
• real-time,
• synchronized actions between field devices like drives,
• efficient, frequent exchange of very small data records.
These new RTE profiles can take advantage of the improvements of Ethernet networks in terms
of transmission bandwidth and network span.
Another implicit but essential requirement is that the typical Ethernet communication
capabilities, as used in the office world, are fully retained, so that the software involved remains
applicable.
The market is in need of several network solutions, each with different performance
characteristics and functional capabilities, matching the diverse application requirements. RTE
performance indicators, whose values will be provided with RTE devices based on
communication profiles specified in the IEC 61784-2 series, enable the user to match network
devices with application-dependent performance requirements of an RTE network.

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IEC 61784-2-0:2023 © IEC 2023 – 7 –
INDUSTRIAL NETWORKS –
PROFILES –

Part 2-0: Additional real-time fieldbus profiles
based on ISO/IEC/IEEE 8802-3 –
General concepts and terminology



1 Scope
The IEC 61784-2 series defines additional Communication Profiles (CPs) for the existing
Communication Profile Families (CPFs) of the IEC 61784-1 series and additional CPFs with one
or more CPs. These additional CPs are based on the IEC 61158 series, the IEC 61784-1 series,
and use provisions from ISO/IEC/IEEE 8802-3 (commonly known as Ethernet) for the lower
communication stack layers. These Real-Time Ethernet (RTE) communication profiles provide
Real-Time Ethernet communication solutions able to coexist with ISO/IEC/IEEE 8802-3 based
applications.
NOTE 1 All CPs are based on standards or draft standards or International Standards published by the IEC or on
standards or International Standards established by other standards bodies or open standards processes.
NOTE 2 The RTE communication profiles use ISO/IEC/IEEE 8802-3 communication networks and its related
network components or IEC 61588 and in some cases amend those standards to obtain RTE features.
This part of IEC 61784-2 defines:
• a common terminology for all CPFs in the IEC 61784-2 series (see 3.1 to 3.3);
• conventions to be used in the specification of the RTE communication profiles (see 3.4);
• how conformance of a device to a CPF or a CP should be stated (see Clause 4).
This document also specifies:
• basic principles of performance indicators expressing RTE performance of a CP (see 5.1);
• how an application-dependent class could be used to find out a suitable CP to meet
application requirements (see 5.2);
• characteristics of RTE performance indicators (see 5.3);
• the methodology of a conformance test for an RTE end device for one or more CPs (see
Clause 6).
2 Normative references
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 All parts of the IEC 61158 series, as well as the IEC 61784-1 series and the IEC 61784-2 series, are
maintained simultaneously. Cross-references to these documents within the text therefore refer to the editions as
dated in this list of normative references.
IEC 61158 (all parts), Industrial communication networks – Fieldbus specifications
IEC 61784-1 (all parts), Industrial networks – Profiles – Part 1: Fieldbus profiles

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– 8 – IEC 61784-2-0:2023 © IEC 2023
IEC 61784-2 (all parts), Industrial networks – Profiles – Part 2: Additional real-time fieldbus
profiles based on ISO/IEC/IEEE 8802-3
ISO/IEC/IEEE 8802-3, Telecommunications and exchange between information technology
systems – Requirements for local and metropolitan area networks – Part 3: Standard for
Ethernet
IEEE Std 802-2014, IEEE Standard for Local and Metropolitan Area Networks: Overview and
Architecture
IEEE Std 802.1AB-2016, IEEE Standard for Local and metropolitan area networks – Station and
Media Access Control Connectivity Discovery
IEEE Std 802.1AS-2020, IEEE Standard for Local and Metropolitan Area Networks – Timing
and Synchronization for Time-Sensitive Applications
IEEE Std 802.1Q-2018, IEEE Standard for Local and Metropolitan Area Networks – Bridges and
Bridged Networks
3 Terms, definitions, abbreviated terms, acronyms, and conventions
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC/IEEE 8802-3,
IEEE Std 802-2014, IEEE Std 802.1AB-2016, IEEE Std 802.1AS-2020, IEEE Std 802.1Q-2018,
and the following, apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
active network
network in which data transmission between non-immediately-connected devices is dependent
on active elements within those intervening devices that form the connection path
[SOURCE: IEC 61918:2018, 3.1.3, modified – The note to entry has been deleted]
3.1.2
cyclic
repetitive in a regular manner
3.1.3
end-station
system attached to a network that is an initial source or a final destination of MAC frames
transmitted across that network
Note 1 to entry: A network layer router is, from the perspective of the network, an end-station. A switch, in its role
of forwarding MAC frames from one link to another, is not an end-station.
3.1.4
field area
place in a manufacturing or process site where field devices are located

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IEC 61784-2-0:2023 © IEC 2023 – 9 –
3.1.5
frame
unit of data transmission on an ISO/IEC/IEEE 8802-3 MAC (Media Access Control) that conveys
a protocol data unit (PDU) between MAC service users
[SOURCE: IEEE Std 802.1Q-2018 – modified in accordance with IEC formatting and
references]
3.1.6
jitter
temporal change in clock signal or temporal change in otherwise regular event
3.1.7
linear topology
topology where the nodes are connected in series, with two nodes connected to only one other
node and all others each connected to two other nodes (that is, connected in the shape of a
line)
[SOURCE: IEC 61918:2018, 3.1.51, modified − The note to entry has been deleted]
3.1.8
link
transmission path between two adjacent nodes
[SOURCE: ISO/IEC 11801-1:2017, 3.1.59, modified – "cabling system interfaces, including the
connections at each end" has been replaced by "nodes" ]
3.1.9
message
ordered series of octets intended to convey information
Note 1 to entry: Normally used to convey information between peers at the application layer.
[SOURCE: IEC 61158-1, 3.1.4, modified – The note to entry has been added]
3.1.10
node
network entity connected to one or more links
Note 1 to entry: A node may be either a switch, an end-station or an RTE end-station.
3.1.11
packet
logical grouping of information used to describe a unit of data at any layer to convey the upper
layer user data to its peer layer
Note 1 to entry: A packet is identical to the PDU at each layer in terms of the OSI reference model. A data-link layer
packet is a frame.
3.1.12
real-time
ability of a system to provide a required result in a bounded time
3.1.13
real-time communication
transfer of data in real time

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3.1.14
Real-Time Ethernet
RTE
ISO/IEC/IEEE 8802-3 based network that includes real-time communication
Note 1 to entry: Other communication can be supported, providing the real-time communication is not compromised.
Note 2 to entry: This definition is dedicated but not limited to ISO/IEC/IEEE 8802-3. It could be applicable to other
IEEE Std 802 specifications, for example IEEE Std 802.11-2020.
3.1.15
ring
active network where each node is connected in series to two other nodes
Note 1 to entry: Ring may also be referred to as loop.
[SOURCE: IEC 61918:2018, 3.1.71, modified – The note to entry has been added]
3.1.16
RTE end device
device with at least one RTE end-station
3.1.17
RTE end-station
end-station with RTE capability
3.1.18
schedule
temporal arrangement of a number of related operations
3.1.19
star
network of three or more devices where all devices are connected to a central point
[SOURCE: IEC 61918:2018, 3.1.77, modified – "(which may be active or passive)" has been
suppressed]
3.1.20
switch
MAC bridge as defined in IEEE Std 802.1Q-2018
3.2 Abbreviated terms and acronyms
AL Application Layer
APDU Application Protocol Data Unit
AR Application Relationship
ARP Address Resolution Protocol
ASE Application Service Element
CP Communication Profile [according to IEC 61784-1-0]
CPF Communication Profile Family [according to IEC 61784-1-0]
DL Data-Link layer (as a prefix)
DLL DL-Layer
DUT Device under test
IANA Internet Assigned Numbers Authority
ICMP Internet Control Message Protocol (see IETF RFC 792)

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IEC 61784-2-0:2023 © IEC 2023 – 11 –
ID Identifier
IETF Internet Engineering Task Force
IO Input Output
IP Internet Protocol (see IETF RFC 791)
LAN Local Area Network
LLC Logical Link Control
LLDP Link Layer Discovery Protocol (see IEEE Std 802.1AB-2016)
MAC Media Access Control (see ISO/IEC/IEEE 8802-3)
Mbit/s Million bits per second
Moctets/s Million octets per second
MIB Management Information base
ms milliseconds
n.a. Not applicable
NoS Number of Switches
NRT Non-real-time
PDU Protocol Data Unit
PI Performance indicator
ns nanoseconds
PDU Protocol Data Unit
PhL Physical Layer
Phy PHY Physical layer entity sublayer (see ISO/IEC/IEEE 8802-3 )
PI Performance indicator
PTP Precision Time Protocol (see IEC 61588)
RSTP Rapid Spanning Tree Algorithm and Protocol (see IEEE Std 802.1Q-2018)
RT Real-time
RTE Real-time Ethernet
SNMP Simple Network Management Protocol (see IETF RFC 1157)
TCP Transmission Control Protocol (see IETF RFC 793)
UDP User Datagram Protocol (see IETF RFC 768)
VLAN Virtual LAN
3
...