IEC 61784-2-16:2023

Industrial networks - Profiles - Part 2-16: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 - CPF 16

IEC 61784-2-16:2023 defines extensions of Communication Profile Family 16 (CPF 16) for Real-Time Ethernet (RTE). CPF 16 specifies a Real-Time Ethernet (RTE) communication profile (CP) and related network components based on the IEC 61158 series (Type 19), ISO/IEC/IEEE 8802-3 and other standards.
For each RTE communication profile, this document also specifies the relevant RTE performance indicators and the dependencies between these RTE performance indicators.
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 profile uses ISO/IEC/IEEE 8802-3 communication networks and its related network components and in some cases amend those standards to obtain RTE features.
NOTE 3 Some CPs of CPF 16 are specified in IEC 61784-1-16.

Réseaux industriels – Profils – Partie 2-16: Profils de bus de terrain supplémentaires pour les réseaux en temps réel fondés sur l’ISO/IEC/IEEE 8802-3 – CPF 16

L’IEC 61784-2-16:2023 définit les extensions de la famille de profils de communication 16 (CPF 16) pour l’Ethernet en temps réel (RTE). La CPF 16 spécifie un profil de communication (CP) Ethernet en temps réel (RTE, Real-Time Ethernet) et des composants de réseau associés basés sur la série IEC 61158 (type 19), l’ISO/IEC/IEEE 8802-3 et d’autres normes.
Pour chaque profil de communication RTE, le présent document spécifie également les indicateurs de performance RTE correspondants et les dépendances entre ces indicateurs de performance RTE.
NOTE 1 Tous les CP sont fondés sur des normes ou projets de normes, ou des Normes internationales, publiés par l’IEC, ou bien sur des normes ou des Normes internationales établies par d’autres organismes de normalisation ou des processus de normalisation ouverts.
NOTE 2 Le profil de communication RTE utilise les réseaux de communication ISO/IEC/IEEE 8802-3 et leurs composants de réseau connexes et amende dans certains cas ces normes, pour obtenir les fonctions RTE.
NOTE 3 Certains CP de la CPF 16 sont spécifiés dans l’IEC 61784-1-16.

General Information

• Status: Published
• Publication Date: 04-May-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: 05-May-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 61784-2-16
®

Edition 1.0 2023-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Industrial networks – Profiles –
Part 2-16: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 –
CPF 16

Réseaux industriels – Profils –
Partie 2-16: Profils de bus de terrain supplémentaires pour les réseaux en temps
réel fondés sur l’ISO/IEC/IEEE 8802-3 – CPF 16

IEC 61784-2-16:2023-05(en-fr)

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IEC 61784-2-16

®


Edition 1.0 2023-05




INTERNATIONAL



STANDARD




NORME


INTERNATIONALE











Industrial networks – Profiles –

Part 2-16: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 –

CPF 16



Réseaux industriels – Profils –

Partie 2-16: Profils de bus de terrain supplémentaires pour les réseaux en


temps réel fondés sur l’ISO/IEC/IEEE 8802-3 – CPF 16













INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 35.100.20; 35.240.50 ISBN 978-2-8322-6905-3




Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

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

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– 2 – IEC 61784-2-16:2023 © IEC 2023
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions, abbreviated terms, acronyms, and conventions . 7
3.1 Terms and definitions . 7
3.2 Abbreviated terms and acronyms . 8
3.3 Symbols . 8
3.4 Conventions . 9
4 CPF 16 (SERCOS) – RTE communication profiles . 9
4.1 General overview . 9
4.2 CP 16/3 (SERCOS III) . 10
4.2.1 Physical layer . 10
4.2.2 Data-link layer . 10
4.2.3 Application layer . 10
4.2.4 Performance indicator selection . 11
Bibliography . 18

Table 1 – CPF 16 symbols . 9
Table 2 – CP 16/3: DLL service selection . 10
Table 3 – CP 16/3: DLL protocol selection . 10
Table 4 – CP 16/3: AL service selection . 10
Table 5 – CP 16/3: AL protocol selection . 11
Table 6 – CP 16/3: PI overview . 11
Table 7 – CP 16/3: PI dependency matrix . 12
Table 8 – CP 16/3: Consistent set of PIs with a minimum cycle time of 31,25 µs . 15
Table 9 – CP 16/3: Consistent set of PIs with a cycle time of 500 µs (real-time only) . 16
Table 10 – CP 16/3: Consistent set of PIs with a cycle time of 500 µs (real-time and
non-real-time) . 17
Table 11 – CP 16/3: Consistent set of PIs with non symmetrical data throughput and a
cycle time of 500 µs (real-time and non-real-time). 17

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IEC 61784-2-16:2023 © IEC 2023 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

INDUSTRIAL NETWORKS –
PROFILES –

Part 2-16: Additional real-time fieldbus profiles
based on ISO/IEC/IEEE 8802-3 –
CPF 16

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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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
rights. IEC shall not be held responsible for identifying any or all such patent rights.
Attention is drawn to the fact that the use of some of the associated protocol types is restricted
by their intellectual-property-right holders. In all cases, the commitment to limited release of
intellectual-property-rights made by the holders of those rights permits a layer protocol type to
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 61784-2-16 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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– 4 – IEC 61784-2-16:2023 © IEC 2023
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.

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IEC 61784-2-16:2023 © IEC 2023 – 5 –
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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– 6 – IEC 61784-2-16:2023 © IEC 2023
INDUSTRIAL NETWORKS –
PROFILES –

Part 2-16: Additional real-time fieldbus profiles
based on ISO/IEC/IEEE 8802-3 –
CPF 16



1 Scope
This part of IEC 61784-2 defines extensions of Communication Profile Family 16 (CPF 16) for
Real-Time Ethernet (RTE). CPF 16 specifies a Real-Time Ethernet (RTE) communication profile
(CP) and related network components based on the IEC 61158 series (Type 19),
ISO/IEC/IEEE 8802-3 and other standards.
For each RTE communication profile, this document also specifies the relevant RTE
performance indicators and the dependencies between these RTE performance indicators.
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 profile uses ISO/IEC/IEEE 8802-3 communication networks and its related
network components and in some cases amend those standards to obtain RTE features.
NOTE 3 Some CPs of CPF 16 are specified in IEC 61784-1-16.
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 61158-3-19:2019, Industrial communication networks – Fieldbus specifications – Part 3-19:
Data-link layer service definition – Type 19 elements
IEC 61158-4-19:2019, Industrial communication networks – Fieldbus specifications – Part 4-19:
Data-link layer protocol specification – Type 19 elements
IEC 61158-5-19:2019, Industrial communication networks – Fieldbus specifications – Part 5-19:
Application layer service definition – Type 19 elements
IEC 61158-6-19:2019, Industrial communication networks – Fieldbus specifications – Part 6-19:
Application layer protocol specification – Type 19 elements
IEC 61784-1-16:2023, Industrial networks – Profiles – Part 1-16: Fieldbus profiles –
Communication Profile Family 16
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

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IEC 61784-2-16:2023 © IEC 2023 – 7 –
IEC 61800 (all parts), Adjustable speed electrical power drive systems
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
IETF RFC 768, J. Postel, User Datagram Protocol, August 1980, available at
https://www.rfc-editor.org/info/rfc768 [viewed 2022-02-18]
IETF RFC 791, J. Postel, Internet Protocol, September 1981, available at
https://www.rfc-editor.org/info/rfc791 [viewed 2022-02-18]
IETF RFC 792, J. Postel, Internet Control Message Protocol, September 1981, available at
https://www.rfc-editor.org/info/rfc792 [viewed 2022-02-18]
IETF RFC 793, J. Postel, Transmission Control Protocol, September 1981, available at
https://www.rfc-editor.org/info/rfc793 [viewed 2022-02-18]
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 IEC 61784-2-0,
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
communication cycle
fixed time period between two master synchronization telegrams
3.1.2
identification number
IDN
designation of operating data under which a data block is preserved with its attribute, name,
unit, minimum and maximum input values, and the data

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– 8 – IEC 61784-2-16:2023 © IEC 2023
3.1.3
IP channel
defined time slot within the communication cycle, which passes ISO/IEC/IEEE 8802-3 Ethernet
protocol frames (non-real-time communication)
3.1.4
master
node which assigns the other nodes the right to transmit
3.1.5
MDT0 telegram
telegram, in which the master transmits its synchronization data, as well as parts or all of its
real-time data, to the slaves
3.1.6
telegram
frame
3.2 Abbreviated terms and acronyms
For the purposes of this document, abbreviated terms and acronyms defined in IEC 61784-2-0
and the following apply.
CP Communication Profile [according to IEC 61784-1-0]
CPF Communication Profile Family [according to IEC 61784-1-0]
ICMP Internet Control Message Protocol (see IETF RFC 792)
IDN IDentification Number
IETF Internet Engineering Task Force
IP Internet Protocol (see IETF RFC 791)
LLDP Link Layer Discovery Protocol (see IEEE Std 802.1AB-2016)
Phy PHY Physical layer entity sublayer (see ISO/IEC/IEEE 8802-3)
PI Performance indicator
RSTP Rapid Spanning Tree Algorithm and Protocol (see IEEE Std 802.1Q-2018)
SERCOS SErial Real time COmmunication System
TCP Transmission Control Protocol (see IETF RFC 793)
UDP User Datagram Protocol (see IETF RFC 768)
3.3 Symbols
For the purposes of this document, symbols defined in IEC 61784-2-0 and Table 1 apply.
NOTE Definitions of symbols in this Subclause 3.3 do not use the italic font, as they are already identified as
symbols.

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IEC 61784-2-16:2023 © IEC 2023 – 9 –
Table 1 – CPF 16 symbols
Symbol Definition Unit
ac Non-time based synchronization accuracy ns
cd Cable delay µs/m
clt Total cable length m
ct Cycle_time configured for the network segment µs
data Data to be transmitted in one cycle (including the complete Ethernet frame) bit
DT Delivery time µs
fr Frame runtime µs
ma Synchronization accuracy of the master device µs
mct Minimum cycle time ms
N Integer value –
nf Number of frames –
nn Number of nodes –
pd Propagation delay (signal delay) of a forwarding node µs
sa Synchronization accuracy of one slave device µs
st Separation time per frame µs
tt Transfer time µs

3.4 Conventions
For the purposes of this document, the conventions defined in IEC 61784-2-0 apply.
1
4 CPF 16 (SERCOS ) – RTE communication profiles
4.1 General overview
Communication Profile Family 16 defines profiles based on IEC 61158 series, protocol Type 16
and Type 19.
The CPF 16 consists of three communication profiles (CP).
– Profile 16/1 (SERCOS I)
This profile is based on fibre-media physical layers and operates at 2 Mbit/s and 4 Mbit/s.
Refer to IEC 61784-1-16.
– Profile 16/2 (SERCOS II)
This profile is similar to 16/1, but operates also at 8 Mbit/s and 16 Mbit/s, and provides for
additional features. Refer to IEC 61784-1-16.
– Profile 16/3 (SERCOS III)
This profile is based on ISO/IEC/IEEE 8802-3 (Ethernet) MAC and physical layers; it
provides again for additional features.
___________
1
 SERCOS is a trade name of Sercos International e.V. This information is given for the convenience of users of
this document and does not constitute an endorsement by IEC of the trademark holder or any of its products.
Compliance with this profile does not require use of the trade name. Use of the trade name requires permission
of the trade name holder.

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4.2 CP 16/3 (SERCOS III)
4.2.1 Physical layer
The physical layer is based on standard Ethernet hardware according to ISO/IEC/IEEE 8802-3.
CP 16/3 (SERCOS III) devices shall use a data rate of 100 Mbit/s, and shall be connected in a
ring or a line topology. Any combination of full-duplex, 100Base-TX with auto crossover function
(wire, 2 twisted pairs), as well as 100Base-FX (optical fibre) may be used.
When using cables, they shall be rated Cat5e or better, and shielded in an appropriate way
(FTP, STP or SFTP) depending upon EMC constraints.
4.2.2 Data-link layer
4.2.2.1 General
CP 16/3 profile shall use standard Ethernet ISO/IEC/IEEE 8802-3 frames tagged with the
Ethertype 0x88CD.
4.2.2.2 DLL service selection
The data-link layer services are defined in IEC 61158-3-19. Table 2 shows the subclauses
included in this profile.
Table 2 – CP 16/3: DLL service selection
Clause Header Presence Constraints
Whole Data link protocol specification (Type 19) YES —
document

4.2.2.3 DLL protocol selection
The data-link layer protocols are defined in IEC 61158-4-19. Table 3 shows the subclauses
included in this profile.
Table 3 – CP 16/3: DLL protocol selection
Clause Header Presence Constraints
Whole Data link protocol specification (Type 19) YES —
document

4.2.3 Application layer
4.2.3.1 AL service selection
The application layer services are defined in IEC 61158-5-19. Table 4 shows the subclauses
included in this profile.
Table 4 – CP 16/3: AL service selection
Clause Header Presence Constraints
Whole Data link protocol specification (Type 19) YES —
document

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IEC 61784-2-16:2023 © IEC 2023 – 11 –
4.2.3.2 AL protocol selection
The application layer protocol is defined in IEC 61158-6-19. Table 5 shows the subclauses
included in this profile.
Table 5 – CP 16/3: AL protocol selection
Clause Header Presence Constraints
Whole Data link protocol specification (Type 19) YES —
document

4.2.4 Performance indicator selection
4.2.4.1 Performance indicator overview
Table 6 gives an overview on the applicable performance indicators for CP 16/3.
Table 6 – CP 16/3: PI overview
Performance indicator Applicable Constraints
Delivery time YES —
Number of end-stations YES —
Basic network topology YES —
Number of switches between end-stations NO Switches shall not be used
Throughput RTE YES —
Non-RTE bandwidth YES —
Time synchronization accuracy NO —
Non-time-based synchronization accuracy YES —
Redundancy recovery time YES In the ring topology, a single permanent
fault does not produce any failure. In this
case, the recovery time is zero

4.2.4.2 Performance indicator dependencies
4.2.4.2.1 Dependency matrix
Table 7 gives an overview on the dependencies of the performance indicators.

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Table 7 – CP 16/3: PI dependency matrix
Influencing PI
Dependent PI
YES NO YES YES NO NO
Delivery time
4.2.4.2.2 4.2.4.2.2 4.2.4.2.2
Number of end-stations YES NO YES YES NO NO
Basic network topology NO NO NO NO NO NO
NO NO NO YES NO NO
Throughput RTE
4.2.4.2.6
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