IEC 61784-2-2:2023
(Main)Industrial networks - Profiles - Part 2-2: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 - CPF 2
Industrial networks - Profiles - Part 2-2: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 - CPF 2
IEC 61784-2-2:2023 defines extensions of Communication Profile Family 2 (CPF 2) for Real-Time Ethernet (RTE). CPF 2 specifies a set of Real-Time Ethernet (RTE) communication profiles (CPs) and related network components based on the IEC 61158 series (Type 2), ISO/IEC/IEEE 8802-3 and other standards.
Réseaux industriels - Profils - Partie 2-2: Profils de bus de terrain supplémentaires pour les réseaux en temps réel fondés sur l’ISO/IEC/IEEE 8802-3 - CPF 2
L' IEC 61784-2-2:2023 définit les extensions de la famille de profils de communication 2 (CPF 2) pour l’Ethernet en temps réel (RTE). La CPF 2 spécifie un jeu de profils de communication (CP) Ethernet en temps réel (RTE) et les composants de réseau connexes basés sur la série IEC 61158 (type 2), l’ISO/IEC/IEEE 8802-3 et d’autres normes.
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IEC 61784-2-2 ®
Edition 1.0 2023-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial networks – Profiles –
Part 2-2: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 –
CPF 2
Réseaux industriels – Profils –
Partie 2-2: Profils de bus de terrain supplémentaires pour les réseaux en temps
réel fondés sur l’ISO/IEC/IEEE 8802-3 – CPF 2
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IEC 61784-2-2 ®
Edition 1.0 2023-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial networks – Profiles –
Part 2-2: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 –
CPF 2
Réseaux industriels – Profils –
Partie 2-2: Profils de bus de terrain supplémentaires pour les réseaux en temps
réel fondés sur l’ISO/IEC/IEEE 8802-3 – CPF 2
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 35.100.20; 35.240.50 ISBN 978-2-8322-6691-5
– 2 – IEC 61784-2-2:2023 © IEC 2023
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions, abbreviated terms, acronyms, and conventions . 9
3.1 Terms and definitions . 9
3.2 Abbreviated terms and acronyms . 9
3.3 Symbols . 9
3.4 Conventions . 10
4 CPF 2 (CIP™) – RTE communication profiles . 10
4.1 General overview . 10
4.2 CP 2/2 . 11
4.2.1 Physical layer . 11
4.2.2 Data-link layer . 11
4.2.3 Application layer . 11
4.2.4 Performance indicator selection . 11
4.3 CP 2/2.1 . 15
4.3.1 Physical layer . 15
4.3.2 Data-link layer . 15
4.3.3 Application layer . 17
4.3.4 Performance indicator selection . 23
Annex A (informative) CPF 2 (CIP) – Performance Indicator calculation . 25
A.1 Profile 2/2 EtherNet/IP . 25
A.1.1 Delivery time . 25
A.1.2 Throughput RTE . 25
A.2 Profile 2/2.1 EtherNet/IP with Time Synchronization. 26
A.2.1 Delivery time . 26
A.2.2 Maximum number of end-stations . 26
Bibliography . 27
Table 1 – CPF 2 symbols . 10
Table 2 – CP 2/2: PI overview . 11
Table 3 – CP 2/2: PI dependency matrix . 12
Table 4 – CP 2/2: Consistent set of PIs for factory automation . 15
Table 5 – CP 2/2.1: DLL protocol selection . 16
Table 6 – CP 2/2.1: DLL protocol selection of management objects . 17
Table 7 – CP 2/2.1: AL service selection . 18
Table 8 – CP 2/2.1: AL protocol selection . 19
Table 9 – ClockIdentity encoding for CP 2/2 . 20
Table 10 – CP 2/2 implementation profiles . 21
Table 11 – Features Supported for Type 2 Ethernet Transports implementation profile . 21
Table 12 – Type 2 Ethernet transport profile supported Features . 22
Table 13 – Supported Encapsulation Commands for transport profiles . 22
Table 14 – CP 2/2.1: PI overview . 23
Table 15 – CP 2/2.1: PI dependency matrix . 24
Table 16 – CP 2/2.1: Consistent set of PIs for motion control . 24
– 4 – IEC 61784-2-2:2023 © IEC 2023
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL NETWORKS –
PROFILES –
Part 2-2: Additional real-time fieldbus profiles
based on ISO/IEC/IEEE 8802-3 –
CPF 2
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
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 61784-2-2 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.
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;
b) addition of two DLL protocol management objects;
c) addition of profile information removed from the Type standards.
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.
– 6 – IEC 61784-2-2:2023 © 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.
INDUSTRIAL NETWORKS –
PROFILES –
Part 2-2: Additional real-time fieldbus profiles
based on ISO/IEC/IEEE 8802-3 –
CPF 2
1 Scope
This part of IEC 61784-2 defines extensions of Communication Profile Family 2 (CPF 2) for
Real-Time Ethernet (RTE). CPF 2 specifies a set of Real-Time Ethernet (RTE) communication
profiles (CPs) and related network components based on the IEC 61158 series (Type 2),
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 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.
NOTE 3 Some CPs of CPF 2 are specified in IEC 61784-1-2.
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 61158-2:2023, Industrial communication networks – Fieldbus specifications – Part 2:
Physical layer specification and service definition
IEC 61158-3-2:2023, Industrial communication networks – Fieldbus specifications – Part 3-2:
Data-link layer service definition – Type 2 elements
IEC 61158-4-2:2023, Industrial communication networks – Fieldbus specifications – Part 4-2:
Data-link layer protocol specification – Type 2 elements
IEC 61158-5-2:2023, Industrial communication networks – Fieldbus specifications – Part 5-2:
Application layer service definition – Type 2 elements
IEC 61158-6-2:2023, Industrial communication networks – Fieldbus specifications – Part 6-2:
Application layer protocol specification – Type 2 elements
IEC 61588:2021, Precision clock synchronization protocol for networked measurement and
control systems
– 8 – IEC 61784-2-2:2023 © IEC 2023
IEC 61784-1-2:2023, Industrial networks – Profiles – Part 1-2: Fieldbus profiles –
Communication Profile Family 2
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 61784-5-2, Industrial communication networks – Profiles – Part 5-2: Installation of
fieldbuses – Installation profiles for CPF 2
IEC 61918, Industrial communication networks – Installation of communication networks in
industrial premises
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]
IETF RFC 826, D. Plummer, An Ethernet Address Resolution Protocol: Or Converting Network
Protocol Addresses to 48.bit Ethernet Address for Transmission on Ethernet Hardware,
November 1982, available at https://www.rfc-editor.org/info/rfc826 [viewed 2022-02-18]
IETF RFC 894, C. Hornig, A Standard for the Transmission of IP Datagrams over Ethernet, April
https://www.rfc-editor.org/info/rfc894 [viewed 2022-02-18]
1984, available at
IETF RFC 1112, S.E. Deering, Host Extensions for IP Multicasting, August 1989, available at
https://www.rfc-editor.org/info/rfc1112 [viewed 2022-02-18]
IETF RFC 1122, R. Braden, Requirements for Internet Hosts – Communication Layers, October
1989, available at https://www.rfc-editor.org/info/rfc1122 [viewed 2022-02-18]
IETF RFC 1123, R. Braden, Requirements for Internet Hosts – Application and Support,
October 1989, available at https://www.rfc-editor.org/info/rfc1123 [viewed 2022-02-18]
IETF RFC 1127, R.T. Braden, Perspective on the Host Requirements RFCs, October 1989,
available at https://www.rfc-editor.org/info/rfc1127 [viewed 2022-02-18]
IETF RFC 2236, W. Fenner, Internet Group Management Protocol, Version 2, November 1997,
available at https://www.rfc-editor.org/info/rfc2236 [viewed 2022-02-18]
IETF RFC 2544, S. Bradner, J. McQuaid, Benchmarking Methodology for Network Interconnect
Devices, March 1999, available at https://www.rfc-editor.org/info/rfc2544 [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
and IEEE Std 802.1Q-2018 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
3.2 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)
IETF Internet Engineering Task Force
IP Internet Protocol (see IETF RFC 791)
LLDP Link Layer Discovery Protocol (see IEEE Std 802.1AB-2016)
PI Performance indicator
pps Packets per second
PTP Precision Time Protocol (see IEC 61588)
RSTP Rapid Spanning Tree Algorithm and Protocol (see IEEE Std 802.1Q-2018)
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.
– 10 – IEC 61784-2-2:2023 © IEC 2023
Table 1 – CPF 2 symbols
Symbol Definition Unit
APDUsize Size of the application protocol data unit per CP 2/2 connection octets
CD Cable segment delay µs
CL Cable segment length m
DT Delivery time µs
EN_NRTE_PR End-station non-RTE packet rate per CP 2/2 connection pps
EN_RTE_PR End-station RTE packet rate per CP 2/2 connection pps
EN_PR End-station packet rate pps
EN_PR_MAX End-station maximum packet rate pps
EN_TNRTE_PR End-station total non-RTE packet rate in pps pps
EN_TRTE_PR End-station total RTE packet rate pps
k Number of CP 2/2 connections supported by the end-station –
m Number of CR 2/2 non-RTE connections –
n Number of switches between sending and receiving end-stations –
p Number of CR 2/2 RTE connections –
NRTE_BW Non-RTE bandwidth %
PD Cable propagation delay n/m
SD Receiver stack delay µs
r
SD Sender stack delay µs
s
SL Switch latency µs
SPD Switch processing delay µs
T Packet transmit time µs
x_packet
3.4 Conventions
For the purposes of this document, the conventions defined in IEC 61784-2-0 apply.
4 CPF 2 (CIP™ ) – RTE communication profiles
4.1 General overview
Communication Profile Family 2 defines several communication profiles based on IEC 61158-2
(protocol type 2), IEC 61158-3-2, IEC 61158-4-2, IEC 61158-5-2, and IEC 61158-6-2, and on
other standards. These profiles all share for their upper layers the same communication system
commonly known as the Common Industrial Protocol (CIP).
___________
CIP™ is a trade name of ODVA, Inc. 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 CIP™. Use of the trade name CIP™ requires permission from
ODVA, Inc.
This document defines two RTE communication profiles.
– Profile 2/2 EtherNet/IP™
This profile contains a selection of AL, DLL and PhL services and protocol definitions from
IEC 61158-4-2, IEC 61158-5-2, and IEC 61158-6-2, and the TCP/UDP/IP/Ethernet protocol
suite. This profile uses the CIP protocol and services in conjunction with the standard
internet and Ethernet standards. This profile provides ISO/IEC/IEEE 8802-3 based real time
communication, through the use of frame prioritization.
– Profile 2/2.1 EtherNet/IP™ with time synchronization
This profile is an extension of CP 2/2 that defines additional mechanisms to provide accurate
time synchronization between nodes using EtherNet/IP. The addition of time synchronization
services and protocols based on IEC 61588 allows using it also for the most demanding
applications.
NOTE 1 See IEC 61784-1-2, Annex A, for an overview of CIP and related networks communications concepts.
NOTE 2 Additional CPs are defined in the other parts of the IEC 61784 series.
4.2 CP 2/2
4.2.1 Physical layer
See IEC 61784-1-2, 4.3.1.
4.2.2 Data-link layer
See IEC 61784-1-2, 4.3.2.
4.2.3 Application layer
See IEC 61784-1-2, 4.3.3.
4.2.4 Performance indicator selection
4.2.4.1 Performance indicator overview
Table 2 provides an overview of CP 2/2 performance indicators.
Table 2 – CP 2/2: PI overview
Performance indicator Applicable Constraints
Delivery time Yes None
Number of end-stations Yes None
Basic network topology Yes Only star topology is supported
Number of switches between end-stations Yes None
Throughput RTE Yes None
Non-RTE bandwidth Yes None
Time synchronization accuracy No –
Non-time-based synchronization accuracy No –
Redundancy recovery time No –
___________
EtherNet/IP™ is a trade name of ODVA, Inc. 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 EtherNet/IP™. Use of the trade name
EtherNet/IP™ requires permission from ODVA, Inc.
– 12 – IEC 61784-2-2:2023 © IEC 2023
4.2.4.2 Performance indicator dependencies
4.2.4.2.1 Dependency matrix
Table 3 shows the dependencies between performance indicators for CP 2/2.
Table 3 – CP 2/2: PI dependency matrix
Influencing PI
Dependent PI
Delivery time NO NO YES NO NO
Number of end-stations NO YES YES NO NO
Basic network topology NO NO NO NO NO
Number of switches YES YES YES NO NO
between end-stations
Throughput RTE NO NO NO NO YES
Non-RTE bandwidth NO NO NO NO YES
4.2.4.2.2 Delivery time
Payload delivery time between any two end-stations depends on many factors as shown below.
For one direction of a CP 2/2 network operating in full-duplex mode, it can be calculated for
each type of application message using Formulae (1), (2) and (3).
nn−1
DT=SD+ T + CD++SL SD (1)
s x_packet ∑∑i k r
i 11k
CD PD×CL
(2)
i ii
q
SL=SPD++T T
(3)
∑
k k x__packet j x_packet
j=1
where
DT is the delivery time in microseconds;
SD is the sender stack delay in microseconds (depending on the selected hardware
s
platform and the embedded software implementation);
T is the packet transmit time in microseconds;
x_packet
n is the number of switches between sending and receiving end-stations;
Delivery
time
Number of
end-
stations
Basic
network
topology
Number of
switches
between
end-station
s
Throughput
RTE
Non-RTE
bandwidth
=
==
CD is the cable segment delay in microseconds;
PD is the cable propagation delay in nanoseconds per meter (depending on the
characteristics of the selected cable);
CL is the cable segment length in meters;
SL is the switch latency in microseconds (measured based on IETF RFC 2544, usually
provided by the switch vendor);
SPD is the switch processing delay in microseconds (provided by the switch vendor
instead of SL);
q is the number packets in the port transmit queue in front on of this packet;
T is the transmit time of packet j;
x_packet_j
SD is the receiver stack delay in microseconds (depending on the selected hardware
r
platform and the embedded software implementation).
NOTE If a packet is lost, e.g. due to a transmission error, but the following one is received without errors, then the
delivery time will double. The CP 2/2 system performance will not be affected unless four consecutive packets are
lost.
4.2.4.2.3 Number of end-stations
With regard to star topology, this document considers network infrastructures containing only
data-link layer (Ethernet) switches. This assumes that all end-stations are connected to the
same subnet. Based on the CP 2/2 specification, a subnet can contain a maximum of 1 024
end-stations. The minimum number of end-stations is two, one producer and one consumer of
the RTE data.
4.2.4.2.4 Basic network topology
The basic topology of the CP 2/2 network is a hierarchical star. Since basic network topology
is given, it is not dependent on, or influenced by, any of the performance indicators.
4.2.4.2.5 Number of switches between end-stations
The number of switches between end-stations, which is the number of layers in a hierarchical
star, is determined on the basis of:
– delivery time;
– number of end-stations, their physical location and the distance between them;
– network traffic profile (types of traffic, rates, traffic mix);
– performance of selected switches, in particular their throughput, their physical location,
distance between them and number of ports per switch;
– network management requirements.
The minimum number is 1. The maximum number is 1 024 where each end-station has an
individual switch, which is similar to the linear topology.
4.2.4.2.6 Throughput RTE
In switched Ethernet networks based on the star topology, a link is a link between an end-
station and a switch port. Based on the definition provided in IEC 61784-2-0, 5.3.5, throughput
RTE depends on the link data rate, link mode of operation (half or full-duplex) and protocol
overhead. Throughput RTE for one direction of a CP 2/2 link operating in a full-duplex mode
can be calculated on the basis of Formula (4).
k
Throughput_RTE= (APDUsize× EN_RTE_PR )≤ EN__PR MAX
(4)
∑
i i
i=1
– 14 – IEC 61784-2-2:2023 © IEC 2023
where
APDUsize is the size of the application protocol data unit per CP 2/2 connection in octets;
EN_RTE_PR is the end-station RTE packet rate per CP 2/2 connection in packets per
second (pps);
k is the number of CP 2/2 connections supported by the end-station;
EN_PR_MAX is the end-station maximum packet rate in pps.
4.2.4.2.7 Non-RTE bandwidth
CP 2/2 does not specify a percentage of bandwidth which can be used for non-RTE
communication but it can be calculated as shown below.
4.2.4.2.8 Relation between throughput RTE and non-RTE bandwidth
A link in the CP 2/2 is a link between an end-station and a switch port. The total link bandwidth
is limited by the end-station throughput, which is the same as the end-station maximum packet
rate. The total link bandwidth is therefore a sum of end-station RTE and non-RTE packet rates
and can be calculated using Formulae (5), (6), (7), (8) and (9).
Total_Link_Bandwidth= EN__PR MAX
(5)
EN_PR=EN_TRTE_PR+ EN_TNRTE_PR≤ EN__PR MAX
(6)
p
EN_TRTE_PR= EN__RTE PR
(7)
∑ i
i=1
m
EN_TNRTE_PR= EN__NRTE PR
∑ (8)
j
j=1
EN__PR MAX− EN_TRTE_PR
NRTE_BW × 100%
(9)
EN__PR MAX
where
EN_PR is the end-station packet rate in packets per second (pps);
EN_PR_MAX is the end-station maximum packet rate in pps;
EN_TRTE_PR is the end-station total RTE packet rate in pps;
EN_RTE_PR is the end-station RTE packet rate per CP 2/2 connection in pps;
p is the number of CR 2/2 RTE connections;
EN_TNRTE_PR is the end-station total non-RTE packet rate in pps;
EN_NRTE_PR is the end-station non-RTE packet rate per CP 2/2 connection in pps;
m is the number of CR 2/2 non-RTE connections;
=
NRTE_BW is the non-RTE bandwidth, in %.
EXAMPLE
End device maximum packet rate is 2 000 pps. It has 5 RTE connections, 2 with EN_RTE_PR = 200 pps and 3 with
EN_RTE_PR = 100 pps. It also has 4 non-RTE connections, all with EN_NRTE_PR = 10 pps.
EN_TRTE_PR= 2× 200pps+×3 100pps= 700pps
EN_PR= 700pps+=40pps 740pps
40pps
NRTE_BW ×=100% 2%
2 000pps
2000pps− 700pps
NRTE_BW 100% 65%
max
2000pps
In this example, 65 % of link bandwidth can be used for non-RTE traffic but only 2 % has actually been used.
4.2.4.3 Consistent set of performance indicators
Table 4 defines a consistent set of performance indicators for CP 2/2. Details for calculating
the performance indicators are given in Annex A. Minimum and maximum values of delivery
time are calculated in A.1.1. The maximum value of the throughput RTE is calculated in A.1.2.
Table 4 – CP 2/2: Consistent set of PIs for factory automation
Performance indicator Value Constraints
Delivery time 130 µs to 20,4 ms –
Number of end-stations 2 to 1 024 –
Number of switches between end-stations 1 to 1 024 –
Throughput RTE –
0 octets/s to 3,44 × 10 octets/s
Non-RTE bandwidth 0 % to 100 % –
4.3 CP 2/2.1
4.3.1 Physical layer
The physical layer of the Ethernet/IP CP 2/2.1 profile is according to ISO/IEC/IEEE 8802-3.
Recommended connectors and cables are specified in IEC 61918 and IEC 61784-5-2.
NOTE 1 EtherNet/IP can be used with a number of media options (e.g. copper, fiber, fiber ring, wireless) in
conjunction with the Ethernet lower layers.
NOTE 2 Additional information is provided in ODVA: THE CIP NETWORKS LIBRARY – Volume 2: EtherNet/IP™
Adaptation of CIP, Chapter 8: Physical Layer.
The time stamping feature for time synchronization is implemented using a hardware assist
circuit as specified in IEC 61588.
4.3.2 Data-link layer
4.3.2.1 DLL service selection
The data-link layer of the CP 2/2.1 profile is according to ISO/IEC/IEEE 8802-3.
×= =
=
– 16 – IEC 61784-2-2:2023 © IEC 2023
4.3.2.2 DLL protocol selection
4.3.2.2.1 General
The data-link layer of the CP 2/2.1 profile is according to ISO/IEC/IEEE 8802-3.
Table 5 specifies the DLL protocol selection within IEC 61158-4-2.
Table 5 – CP 2/2.1: DLL protocol selection
Clause Header Presence Constraints
1 Scope YES —
1.1 General YES —
1.2 – 1.3 — NO —
1.4 Applicability YES —
1.5 Conformance YES —
2 Normative references YES —
3 Terms, definitions, symbols, abbreviated terms and YES —
conventions
4 – 5 — NO —
6 Specific DLPDU structure, encoding and — —
procedures
6.1 Modeling language YES —
Next — NO —
subclauses
7 Objects for station management — See Table 6
8 – 9 — NO —
10 Device Level Ring (DLR) protocol YES Optional
11 PRP and HSR redundancy protocols YES Optional
12 LLDP protocol YES Optional for legacy devices,
otherwise required
Annex A (normative) – Indicators and switches — —
A.1 Purpose YES —
A.2 Indicators — —
A.2.1 General indicator requirements YES —
A.2.2 Common indicator requirements YES —
A.2.3 Fieldbus specific indicator requirements (1) NO —
A.2.4 Fieldbus specific indicator requirements (2) YES —
A.2.5 Fieldbus specific indicator requirements (3) NO —
A.3 Switches — —
A.3.1 Common switch requirements YES —
A.3.2 Fieldbus specific switch requirements (1) NO —
A.3.3 Fieldbus specific switch requirements (2) YES —
A.3.4 Fieldbus specific switch requirements (3) NO —
Table 6 specifies the management objects selection.
Table 6 – CP 2/2.1: DLL protocol selection of management objects
Clause Header Presence Constraints
7 Objects for station management – –
7.1 General Partial Relevant objects and features only
7.2 – 7.4 — NO —
7.5 TCP/IP interface object YES —
7.6 Ethernet link object YES —
7.7 DeviceNet object NO —
7.8 Connection configuration object YES —
7.9 DLR object YES Optional (required if DLR protocol is
implemented)
7.10 QoS object YES Optional
7.11 Port object YES See 4.3.2.2.2
7.12 PRP/HSR Protocol object YES Optional (required if PRP/HSR
protocol is implemented)
7.13 PRP/HSR Nodes Table object YES Optional (required if PRP/HSR
protocol is implemented)
7.14 LLDP Management object YES Optional (required if LLDP protocol is
implemented)
7.15 LLDP Data Table object YES Optional, and only if LLDP protocol is
implemented
4.3.2.2.2 Port object
The Port object refers to a logical link/network interface on the device, i.e. the interface used
to address it. For CP 2/2.1, the logical link address is the IP Address (reflected in the TCP/IP
object), not the Ethernet MAC_ID.
4.3.3 Application layer
4.3.3.1 AL service selection
4.3.3.1.1 General
Table 7 specifies the AL service selection within IEC 61158-5-2.
– 18 – IEC 61784-2-2:2023 © IEC 2023
Table 7 – CP 2/2.1: AL service selection
Clause Header Presence Constraints
1 Scope YES —
2 Normative references YES —
3 Terms, definitions, symbols, abbreviated YES —
terms and conventions
4 Common concepts Partial Differences are indicated in
IEC 61158-5-2, 6.1
5 Data type ASE Partial Selection and restrictions are
specified in IEC 61158-5-2, 6.1
6 Communication model specification — —
6.1 Concepts YES —
6.2 ASEs — —
6.2.1 Object management ASE — —
6.2.1.1 Overview YES —
6.2.1.2 FAL management model class specification — —
6.2.1.2.1 General formal model YES —
6.2.1.2.2 Identity formal model YES Required
6.2.1.2.3 Assembly formal model YES —
6.2.1.2.4 Message Router formal model YES Required
6.2.1.2.5 Acknowledge Handler formal model YES —
6.2.1.2.6 Time Sync formal model YES Required. See 4.3.3.1.2
6.2.1.2.7 Parameter formal model YES —
6.2.1.3 FAL management model ASE service YES —
specification
6.2.2 Connection manager ASE YES Single class in this ASE
Required (every device shall
implement instance 1)
6.2.3 Connection ASE YES Optional (internal or external)
6.3 AR's — —
6.3.1 Overview YES —
6.3.2 UCMM AR formal model NO —
6.3.3 Transport AR formal model YES —
6.3.4 AR ASE services YES —
6.4 Summary of FAL classes YES —
6.5 Permitted FAL services by AR type YES —
In addition, AL services are mapped onto the TCP/UDP/IP protocol suite.
The corresponding minimum requirements for EtherNet/IP devices are as specified in
IETF RFC 1122, IETF RFC 1123, IETF RFC 1127 and subsequent documents that may
supersede them. All EtherNet/IP devices shall as a minimum support requirements specified in
IETF RFC 768, IETF RFC 791, IETF RFC 792, IETF RFC 793, IETF RFC 826 and
IETF RFC 894.
EtherNet/IP devices that support consumption of Type 2 Class 0/1 multicast connections (see
IGMP Usage in IEC 6
...
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