SC 65C - Industrial networks

IEC 61784-3:2021 explains some common principles that can be used in the transmission of safety-relevant messages among participants within a distributed network which use fieldbus technology in accordance with the requirements of IEC 61508 (all parts) for functional safety. These principles are based on the black channel approach. They can be used in various industrial applications such as process control, manufacturing automation and machinery.

IEC 61784-5-8:2024 is available as IEC 61784-5-8:2024 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 61784-5-8:2024 specifies the installation profiles for CPF 8 (CC-LinkTM[1]). The installation profiles are specified in the annexes. These annexes are read in conjunction with IEC 61918:2018, IEC 61918:2018/AMD1:2022 and IEC 61918:2018/AMD2:2024.
[1] CC-Link™, CC-Link/LT™ and CC‑Link IE™ are trade names of Mitsubishi Electric Co., control of trade name use is given to CCLink Partner Association. 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 to this profile does not require use of the trade name. Use of the trade name requires permission of the trade name holder.

IEC 61784-5-6:2024 is available as IEC 61784-5-6:2024 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 61784-5-6:2024 specifies the installation profiles for CPF 6 (INTERBUSTM)[1]. The installation profiles are specified in the annexes. These annexes are read in conjunction with IEC 61918:2018, IEC 61918:2018/AMD1:2022 and IEC 61918:2018/AMD2:2024.
[1] INTERBUSTM is a trade name of INTERBUS Club, an independent organisation of users and vendors of INTERBUS products. 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 to this profile does not require use of the trade name INTERBUS. Use of the trade name INTERBUS requires permission of the trade name holder.

IEC 61784-5-19:2024 is available as IEC 61784-5-19:2024 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 61784-5-19:2024 specifies the installation profile for CPF 19 (MECHATROLINKTM[1]). The installation profiles are specified in the annexes. These annexes are read in conjunction with IEC 61918:2018, IEC 61918:2018/AMD1:2022 and IEC 61918:2018/AMD2:2024.
[1] MECHATROLINKTM and Σ-LINKTM II are trade names of YASKAWA ELECTRIC CORPORATION. This information is given for the convenience of users of this document and does not constitute an endorsement by IEC of the trade names holder or any of its products. Compliance to this profile does not require use of the trade names. Use of the trade name requires permission of the trade name holder.

IEC 61784-5-3:2018 specifies the installation profiles for CPF 3 (PROFIBUS/PROFINET).
This contribution contains a number of related files covering the communication profiles to be used in conjunction with IEC 61918.
This installation profile documents contained herewith provide the installation profiles of the communication profiles (CP) of a specific communication profile family (CPF) by stating which requirements of IEC 61918 fully apply and, where necessary, by supplementing, modifying, or replacing the other requirements. The installation profiles are specified in the annexes. These annexes are read in conjunction with IEC 61918. This fourth edition cancels and replaces the third edition published in 2013. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) an addition of 4-pair cabling (see C.4.4.1.2.1and C.5.3.2);
b) an addition of the connector M12 X-Coding (see C.4.4.2.2);
c) an addition of the definition of End-to-end links (see C.4.4.3.1);
d) a revision of Table C.17 (see C.5.2.1);
e) a formula for the NEXT limits of End-to-end links (see C.6.3.2.1.2).

IEC 61784-5-X: 2023 (EN) is one of a series produced to facilitate the use of communication networks in industrial control systems.

IEC 61784-5-21:2018 specifies the installation profiles for CPF 21 (FL-net).
This contribution contains a number of related files covering the communication profiles to be used with IEC 61918.
This installation profile documents contained herewith provide the installation profiles of the communication profiles (CP) of a specific communication profile family (CPF) by stating which requirements of IEC 61918 fully apply and, where necessary, by supplementing, modifying, or replacing the other requirements. The installation profiles are specified in Annex A. This annex is read in conjunction with IEC 61918.

IEC 61784-5-X: 2023 (EN) is one of a series produced to facilitate the use of communication networks in industrial control systems.

IEC 61784-5-X: 2023 (EN) is one of a series produced to facilitate the use of communication networks in industrial control systems.

IEC 61784-5-2:2018 specifies the installation profiles for CPF 2 (CIP™ ). This contribution contains a number of related files covering the communication profiles to be used in conjunction with IEC 61918. The installation profile documents contained herewith provide the installation profiles of the communication profiles (CP) of a specific communication profile family (CPF) by stating which requirements of IEC 61918 fully apply and, where necessary, by supplementing, modifying, or replacing the other requirements. The installation profiles are specified in the annexes. These annexes are read in conjunction with IEC 61918. This fourth edition cancels and replaces the third edition published in 2013. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) references to ISO/IEC 24702 have been replaced with references to ISO/IEC 11801-3 in Table B.1;
b) errors have been corrected;
c) Tables B11 and B13 have been added in support of 1,000 Mb/s 4 Pair Ethernet;
d) Clarification of dual power supplies for Annex C.

IEC 61784-5-12:2024 is available as IEC 61784-5-12:2024 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 61784-5-12:2024 specifies the installation profile for CPF 12 (EtherCAT™).
The installation profile is specified in Annex A. This annex is read in conjunction with IEC 61918:2018, IEC 61918:2018/AMD1:2022 and IEC 61918:2018/AMD2:2024.
EtherCAT™ is a trade name of Beckhoff, Verl. 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 to this profile does not require use of the trade name. Use of the trade name requires permission of the trade name holder.

IEC 61918:2018 specifies basic requirements for the installation of media for communication networks in industrial premises and within and between the automation islands, of industrial sites. This standard covers balanced and optical fibre cabling. It also covers the cabling infrastructure for wireless media, but not the wireless media itself. Additional media are covered in the IEC 61784-5 series.
This fourth edition cancels and replaces the third edition published in 2013. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) the reference to ISO/IEC 24702 has been replaced with reference to the new ISO/IEC 11801-3; this affects Table 2;
b) some terms and abbreviated terms have been modified in Clause 3;
c) Subclauses 4.1.2, 4.4.2.5, 4.4.3.4.1 and 5.7 have been updated;
d) Figure 2 and Figure 3 have been updated; Figure 13, Figure 16, Figure 30 and Figure 49 have been added;
e) Table 7 has been updated;
f) Annex D and Annex M have been extended to cover additional communication profile families; Annex H has been extended to cover the M12-8 X-coding connector use;
g) Annex O has been modified by including references to the new edition of the
ISO/IEC 11801 series, ISO/IEC TR 11801-9902 and ISO/IEC 14763-4;
h) Annex P has been added.
This standard is to be used in conjunction with the IEC 61784-5 series with regard to the installation of communication profiles (CPs).

IEC 61784-5-22:2024 specifies the installation profile for CPF 22 (AUTBUSTM [1]).
The installation profile is specified in Annex A. This annex is read in conjunction with IEC 61918:2018, IEC 61918:2018/AMD1:2022 and IEC 61918:2018/AMD2:2024.
[1] AUTBUSTM is the trade name of the Kyland Technology Co., Ltd. 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 does not require use of the trade name. Use of the trade name requires permission of Kyland Technology Co., Ltd.

IEC TS 63444:2023 is applicable to process automation equipment using a 10BASE-T1L compliant (see IEEE Std 802.3-2022, Clause 146) Physical Layer (PHY). Ethernet-APL intrinsically safe profiles with different predefined entity or limitation parameters (for example voltage, current, power, capacitance, inductance, cable length) simplify the examination of the interconnection of different Ethernet-APL ports.
The following technical features are part of this document:
- topology with trunk/spur installation capability;
- 2-wire technology (full-duplex communication data rate of 10 Mbit/s);
- long distance (refers to cable lengths of several hundred meters, with spans up to 1 000 m);
- intrinsic safety (installation of Ethernet-capable field devices in hazardous areas);
- power supply to field devices over the same 2-wire cable used for data communication.

IEC 61139-3:2023 specifies a wireless single-drop digital communication interface (SDCI wireless).
This is an extension to the single-drop digital communication interface (SDCI) technology that is specified in IEC 61131-9.
This document specifies the wireless communication services and protocol (physical layer, data link layer and application layer in accordance with the ISO/OSI reference model) for W‑Masters and W‑Devices.
NOTE This document does not cover the integration into higher level systems such as fieldbuses.

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.

IEC 61784-2-13:2023 defines Communication Profile Family 13 (CPF 13). CPF 13 specifies a Real-Time Ethernet (RTE) communication profile (CP) and related network components based on the IEC 61158 series (Type 13), 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 use ISO/IEC/IEEE 8802-3 communication networks and its related network components and in some cases amend those standards to obtain RTE features.

IEC 61784-2-21:2023 defines Communication Profile Family 21 (CPF 21). CPF 21 specifies a Real-Time Ethernet (RTE) communication profile (CP) and related network components based on the IEC 61158 series (Type 26), 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.

IEC 61784-2-14:2023 defines Communication Profile Family 14 (CPF 14). CPF 14 specifies a set of Real-Time Ethernet (RTE) communication profiles (CPs) and related network components based on the IEC 61158 series (Type 14), 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.

IEC 61784-2-11:2023 defines Communication Profile Family 11 (CPF 11). CPF 11 specifies a set of Real-Time Ethernet (RTE) communication profiles (CPs) and related network components based on the IEC 61158 series (Type 11), 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.

IEC 61784-2-12:2023 defines Communication Profile Family 12 (CPF 12). CPF 12 specifies a set of Real-Time Ethernet (RTE) communication profiles (CPs) and related network components based on the IEC 61158 series (Type 12), 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 and in some cases amend those standards to obtain RTE features.

IEC 61784-2-20:2023 defines Communication Profile Family 20 (CPF 20). CPF 20 specifies a set of Real-Time Ethernet (RTE) communication profiles (CPs) and related network components based on the IEC 61158 series (Type 25), 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 and in some cases amend those standards to obtain RTE features.

IEC 61784-2-15:2023 defines Communication Profile Family 15 (CPF 15). CPF 15 specifies a set of Real-Time Ethernet (RTE) communication profiles (CPs) and related network components based on the IEC 61158 series (Type 15), 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 and in some cases amend those standards to obtain RTE features.

IEC 61784-2-17:2023 defines Communication Profile Family 17 (CPF 17). CPF 17 specifies a Real-Time Ethernet (RTE) communication profile (CP) and related network components based on the IEC 61158 series (Type 21), 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.

IEC 61784-2-4:2023 defines extensions of Communication Profile Family 4 (CPF 4) for Real-Time Ethernet (RTE). CPF 4 specifies a Real-Time Ethernet (RTE) communication profile (CP) and related network components based on the IEC 61158 series (Type 4), ISO/IEC/IEEE 8802-3 and other standards

IEC 61784-2-8:2023 defines extensions of Communication Profile Family 8 (CPF 8) for Real-Time Ethernet (RTE). CPF 8 specifies a set of Real-Time Ethernet (RTE) communication profiles (CPs) and related network components based on the IEC 61158 series (Type 23), ISO/IEC/IEEE 8802-3 and other standards.

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.

IEC 61784-2-6:2023 defines extensions of Communication Profile Family 6 (CPF 6) for Real-Time Ethernet (RTE). CPF 6 specifies a set of Real-Time Ethernet (RTE) communication profiles (CPs) and related network components based on the IEC 61158 series (Type 8 and Type 10), ISO/IEC/IEEE 8802-3 and other standards.

IEC 61784-2-3:2023 defines extensions of Communication Profile Family 3 (CPF 3) for Real-Time Ethernet (RTE). CPF 3 specifies a set of Real-Time Ethernet (RTE) communication profiles (CPs) and related network components based on the IEC 61158 series (Type 10), 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.

IEC 61158-4-24:2023 provides
procedures for the timely transfer of data and control information from one data-link user entity to a peer user entity, and among the data-link entities forming the distributed datalink service provider;
procedures for giving communications opportunities to all participating DL-entities (DLEs), sequentially and in a cyclic manner for deterministic and synchronized transfer at cyclic intervals up to 64 ms;
procedures for giving communication opportunities available for time-critical data transmission together with non-time-critical data transmission without prejudice to the time-critical data transmission;
procedures for giving cyclic and acyclic communication opportunities for time-critical data transmission with prioritized access;
procedures for giving communication opportunities based on ISO/IEC/IEEE 8802‑3 medium access control, with provisions for nodes to be added or removed during normal operation;
the structure of the fieldbus DLPDUs used for the transfer of data and control information by the protocol of this document, and their representation as physical interface data units.

IEC 61158-6-26:2023 provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 26 fieldbus. The term "time-critical" is used to represent the presence of a time-window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life.

IEC 61158-4-21:2023 describes:
procedures for the timely transfer of data and control information from one data link user entity to a peer user entity, and among the data link entities forming the distributed data link service provider;
procedures for giving communication opportunities based on ISO/IEC/IEEE 8802‑3 MAC, with provisions for nodes to be added or removed during normal operation;
structure of the fieldbus data link protocol data units (DLPDUs) used for the transfer of data and control information by the protocol of this document, and their representation as physical interface data units.

IEC 61158-5-10:2023 provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 10 fieldbus. The term "time-critical" is used to represent the presence of a time-window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life.

IEC 61784-1-0:2023 series defines several Communication Profile Families (CPF). Each CPF specifies a set of protocol specific communication profiles (CPs) based primarily on the IEC 61158 series, to be used in the design of devices involved in communications in factory manufacturing and process control.
This part of IEC 61784-1 defines a common terminology for all CPFs and conventions to be used in the specification of the CPs. It also provides a compliance statement and an overview of the structure and contents of the CPFs in the IEC 61784-1 series.

IEC 61158-5-2:2023 provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 2 fieldbus. The term "time-critical" is used to represent the presence of a time-window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life.

IEC 61158-6-10:2023 provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 10 fieldbus. The term “time-critical” is used to represent the presence of a time window, within which one or more specified actions are required to be completed with a defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life.

IEC 61158-5-4:2023 provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 4 fieldbus. The term "time-critical" is used to represent the presence of a time-window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life.

IEC 61784-1-16:2023 defines Communication Profile Family 16 (CPF 16). CPF 16 specifies a set of protocol specific communication profiles (CPs) based on the IEC 61158 series (Type 16 and Type 19) and other standards, to be used in the design of devices involved in communications in factory manufacturing and process control.
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 Some CPs of CPF 16 are specified in IEC 61784-2-16.
Each CP selects an appropriate consistent and compatible subset of services and protocols from the relevant set that is defined and modelled in the IEC 61158 series. For the selected subset of services and protocols, the profile also describes any possible or necessary constraints in parameter values.

IEC 61158-6-4:2023 provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 4 fieldbus. The term “time-critical” is used to represent the presence of a time-window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life.

IEC 61784-1-9:2023 defines Communication Profile Family 9 (CPF 9). CPF 9 specifies a set of protocol specific communication profiles (CPs) based on the IEC 61158 series (Type 20) and other standards, to be used in the design of devices involved in communications in factory manufacturing and process control.
NOTE 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.
Each CP selects an appropriate consistent and compatible subset of services and protocols from the relevant set that is defined and modelled in the IEC 61158 series. For the selected subset of services and protocols, the profile also describes any possible or necessary constraints in parameter values.

IEC 61784-1-19:2023 defines Communication Profile Family 19 (CPF 19). CPF 19 specifies a set of protocol specific communication profiles (CPs) based on the IEC 61158 series (Type 24 and Type 27) and other standards, to be used in the design of devices involved in communications in factory manufacturing and process control.
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 Some CPs of CPF 19 are specified in IEC 61784-2-19.
Each CP selects an appropriate consistent and compatible subset of services and protocols from the relevant set that is defined and modelled in the IEC 61158 series. For the selected subset of services and protocols, the profile also describes any possible or necessary constraints in parameter values.

IEC 61158-6-28:2023 provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 28 fieldbus. The term "time-critical" is used to represent the presence of a time-window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window can cause failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life.

IEC 61158-6-2:2023 provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 2 fieldbus. The term "time-critical" is used to represent the presence of a time-window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life.

IEC 61158-6-24:2023 provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 24 fieldbus. The term "time-critical" is used to represent the presence of a time-window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life.

IEC 61158-6-23:2023 provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 23 fieldbus. The term "time-critical" is used to represent the presence of a time-window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life.

IEC 61158-4-4:2023 specifies
- procedures for the timely transfer of data and control information from one data-link user entity to a peer user entity, and among the data-link entities forming the distributed data-link service provider;
- the structure of the fieldbus DLPDUs used for the transfer of data and control information by the protocol of this document, and their representation as physical interface data units.