IEC 61158-4-4:2019

IEC 61158-4-4 ®
Edition 3.0 2019-04
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 4-4: Data-link layer protocol specification – Type 4 elements

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IEC 61158-4-4 ®
Edition 3.0 2019-04
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –

Part 4-4: Data-link layer protocol specification – Type 4 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.100.20; 35.110 ISBN 978-2-8322-6774-5

– 2 – IEC 61158-4-4:2019 © IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
1.1 General . 7
1.2 Specifications . 7
1.3 Procedures . 7
1.4 Applicability . 7
1.5 Conformance . 7
2 Normative references . 8
3 Terms, definitions, symbols and abbreviations . 8
3.1 Reference model terms and definitions . 8
3.2 Service convention terms and definitions . 10
3.3 Terms and definitions. 11
3.4 Symbols and abbreviations . 14
4 Data Link Protocol Definition . 14
4.1 Overview of the DL-protocol . 14
4.2 General structure and encoding of PhIDUs and DLPDUs, and related
elements of procedure . 26
4.3 DLPDU-specific structure, encoding and elements of procedure . 33
4.4 DL-service elements of procedure . 37
4.5 Route mechanism . 40
4.6 Link-access system . 43
4.7 Local variables, counters and queues . 44
Bibliography . 46

Figure 1 – Relationship of PhE, DLE and DLS-user . 15
Figure 2 – DLE state diagram for confirmed and unconfirmed, unacknowledged
DLPDUs . 17
Figure 3 – DLE state diagram for confirmed acknowledged DLPDUs . 18
Figure 4 – DLE state diagram for unconfirmed acknowledged DLPDUs . 19
Figure 5 – Full duplex DLE receive state diagram . 20
Figure 6 – Full duplex DLE transmit state diagram . 20
Figure 7 – Link access example . 23
Figure 8 – Simple Type 4-route format . 29
Figure 9 – Extended Type 4-route format . 29
Figure 10 – Complex Type 4-route format . 30
Figure 11 – Immediate Type 4-route format . 30
Figure 12 – IP Type 4-route format . 31
Figure 13 – Control-status format. 32
Figure 14 – Data-field-format . 32
Figure 15 – Source / destination designator . 41
Figure 16 – Simple Type 4-route generation . 41
Figure 17 – Extended Type 4-route generation . 41
Figure 18 – Complex and IP Type 4-route generation . 42
Figure 19 – Simple DL-route generation . 42

Figure 20 – Extended DL-route generation . 43
Figure 21 – Complex and IP DL-route generation . 43

Table 1 – Summary structure of DLPDUs . 33
Table 2 – Structure of confirmed DLPDUs . 34
Table 3 – Structure of unconfirmed DLPDUs . 35
Table 4 – Structure of acknowledge DLPDU . 36
Table 5 – Structure of immediate-reply DLPDU . 36

– 4 – IEC 61158-4-4:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 4-4: Data-link layer protocol specification –
Type 4 elements
FOREWORD
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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 the associated protocol type is restricted by its
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 its intellectual-property-right holders.
NOTE Combinations of protocol types are specified in IEC 61784-1 and IEC 61784-2.
International Standard IEC 61158-4-4 has been prepared by subcommittee 65C: Industrial
networks, of IEC technical committee 65: Industrial-process measurement, control and
automation.
This third edition cancels and replaces the second edition published in 2014. This edition
constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous
edition:
a) additional user parameters to services;
b) additional services to support distributed objects;
c) additional secure services;
The text of this International Standard is based on the following documents:
FDIS Report on voting
65C/946/FDIS 65C/955/RVD
Full information on the voting for the approval of this International standard can be found in
the report on voting indicated in the above table.
This publication has been drafted in accordance with ISO/IEC Directives, Part 2.
A list of all the parts of the IEC 61158 series, published under the general title Industrial
communication networks – Fieldbus specifications, can be found on the IEC website.
The committee has decided that the contents of this publication will rem
...