IEC TS 61158-5:1999

TECHNICAL
IEC
SPECIFICATION
61158-5
First edition
1999-03
Digital data communications for
measurement and control —
Fieldbus for use in industrial control systems
Part 5:
Application Layer Service definition

Reference number
IEC 61158-5:1999(E)
Numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series.
Consolidated publications
Consolidated versions of some IEC publications including amendments are

available. For example, edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the
base publication, the base publication incorporating amendment 1 and the base

publication incorporating amendments 1 and 2.

Validity of this publication
The technical content of IEC publications is kept under constant review by the IEC,
thus ensuring that the content reflects current technology.
Information relating to the date of the reconfirmation of the publication is available
in the IEC catalogue.
Information on the subjects under consideration and work in progress undertaken by
the technical committee which has prepared this publication, as well as the list of
publications issued, is to be found at the following IEC sources:
• IEC web site*
• Catalogue of IEC publications
Published yearly with regular updates
(On-line catalogue)*
• IEC Bulletin
Available both at the IEC web site* and as a printed periodical
Terminology, graphical and letter symbols
For general terminology, readers are referred to IEC 60050: International
Electrotechnical Vocabulary (IEV).
For graphical symbols, and letter symbols and signs approved by the IEC for
general use, readers are referred to publications IEC 60027: Letter symbols to be
used in electrical technology, IEC 60417: Graphical symbols for use on equipment.
Index, survey and compilation of the single sheets and IEC 60617: Graphical symbols
for diagrams.
* See web site address on title page.

TECHNICAL IEC
SPECIFICATION 61158-5
First edition
1999-03
Digital data communications for
measurement and control —
Fieldbus for use in industrial control systems
Part 5:
Application Layer Service definition

© IEC 1999 – Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
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International Electrotechnical Commission

For price, see current catalogue

– 2 – 61158-5 © IEC:1999
Contents
Page
FOREWORD .7

INTRODUCTION .9

Clause
1 SCOPE.10

2 NORMATIVE REFERENCES .11
3 DEFINITIONS.12
3.1 ISO/IEC 7498 terms.12
3.2 ISO/IEC 8822 terms.12
3.3 ISO/IEC 9545 terms.12
3.4 ISO/IEC 8824 terms.12
3.5 Fieldbus Data Link Layer terms .12
3.6 FAL Specific Definitions.13
3.6.1 Application Object Definition .13
3.6.2 Application Process Object Class Definition .13
3.6.3 Application Relationship Definition .13
3.6.4 Application Relationship Application Service Element Definition .13
3.6.5 Application Relationship Endpoint Definition.13
3.6.6 Client Definition .13
3.6.7 Conveyance Path Definition .13
3.6.8 Dedicated AR Definition .13
3.6.9 Dynamic AR Definition 14
3.6.10 Error Class Definition .14
3.6.11 Error Code Definition.14
3.6.12 Invocation Definition.14
3.6.13 Application Layer Interoperability Definition .14
3.6.14 Management Information Definition.14
3.6.15 Peer Definition.14
3.6.16 Pre-defined AR Endpoint Definition .14
3.6.17 Pre-established AR Endpoint Definition.14
3.6.18 Publisher Definition .14
3.6.19 Publishing Manager Definition .14
3.6.20 Pull Publisher Definition .15
3.6.21 Pull Publishing Manager Definition .15
3.6.22 Push Publisher Definition.15
3.6.23 Push Publishing Manager Definition .15

3.6.24 Pull Subscriber Definition.15
3.6.25 Push Subscriber Definition.15
3.6.26 Resource Definition.15
3.6.27 Server Definition.15
3.6.28 Subscriber Definition.15
3.7 Abbreviations and Symbols .15
3.8 Conventions.16
3.8.1 General Conventions.16
3.8.2 Conventions for Class Definitions .17
3.8.3 Conventions for Service Definitions .18
4 CONCEPTS .20
4.1 Architectural Relationships .20
4.1.1 Overview .20
4.1.2 Relationship to the Application Layer of the OSI Reference Model .20

61158-5 © IEC:1999 – 3 –
Clause Page
4.1.3 Relationships to Other Fieldbus Standards.21

4.2 Fieldbus Application Layer Structure .22

4.2.1 Overview .22

4.2.2 Fundamental Concepts.22

4.2.3 Fieldbus Application Processes .22

4.2.4 Application Objects .26
4.2.5 Application Entities.28
4.2.6 Fieldbus Application Service Elements .29

4.2.7 Application Relationships .32

4.3 Fieldbus Application Layer Naming and Addressing .35

4.3.1 Identifying Objects Accessed Through the FAL.35

4.3.2 Addressing APs Accessed Through the FAL.36

4.4 Architecture Summary.37
4.5 FAL Service Procedures and Time Sequence Diagrams.37
4.5.1 FAL Confirmed Service Procedures .37
4.5.2 Confirmed Service Time Sequence Diagram.38
4.5.3 FAL Unconfirmed Service Procedures.39
4.5.4 Unconfirmed Service Time Sequence Diagram.39
4.6 Common FAL Attributes .39
4.7 Common FAL Service Parameters.40
4.8 APDU Size.42
5 OBJECT MANAGEMENT ASE .43
5.1 Overview.43
5.2 FAL Management Model Specification.43
5.3 FAL Management Model Services.43
5.3.1 Create Service .43
5.3.2 Delete Service.44
5.3.3 Get Attributes Service .46
5.3.4 Set Attributes Service.48
5.3.5 Begin Set Attributes Service.50
5.3.6 End Set Attributes Service .51
6 APPLICATION PROCESS ASE .52
6.1 Overview.52
6.2 AP Class Specification.52
6.2.1 AP Formal Model .52
6.3 Application Process ASE Service Specification.60
6.3.1 Subscribe Service .60
6.3.2 Identify Service.64
6.3.3 Get Status Service .65
6.3.4 Status Notification Service .66
6.3.5 Initiate Service.67
6.3.6 Terminate Service.71

6.3.7 Conclude Service .73
6.3.8 Reject Service .74
7 APPLICATION RELATIONSHIP ASE .76
7.1 Overview.76
7.1.1 Endpoint Context.76
7.1.2 Underlying Communications Services .79
7.1.3 AR Establishment.80
7.1.4 Application Relationship Classes .80
7.2 Application Relationship Endpoint Class Specifications .81
7.2.1 AR Endpoint Formal Model .81
7.3 Application Relationship ASE Service Specifications .82
7.3.1 AR-Unconfirmed Send Service .82
7.3.2 AR-Confirmed Send Service.84
7.3.3 AR-Establish Service .86

– 4 – 61158-5 © IEC:1999
Clause Page
7.3.4 AR-DeEstablish Service.88

7.3.5 AR-Abort Service.89

7.3.6 AR-Compel Service.91

7.3.7 AR-Get Buffered Message Service .92

7.3.8 AR-Schedule Communication Service .93

7.3.9 AR-Cancel Scheduled Sequence Service.94
7.3.10 AR-Get DL-Time Service .95
7.3.11 AR-Status Service.95

7.3.12 AR-XON-OFF Service.96

7.3.13 AR Remote Read Service.97

7.3.14 AR-Remote Write Service.98

8 DATA TYPE ASE.100
8.1 Overview.100
8.1.1 Overview of Basic Types.101
8.1.2 Overview of Constructed Types .101
8.1.3 Specification of User Defined Data Types .102
8.1.4 Transfer of User Data.102
8.2 Formal Definition of Data Type Objects.102
8.2.1 Data Type Class.102
8.3 FAL Defined Data Types.104
8.3.1 Fixed Length Types.104
8.3.2 String Types .113
8.4 Data Type ASE Service Specification.114
9 VARIABLE ASE .115
9.1 Overview.115
9.1.1 Requirements for Access to Variables.116
9.2 Variable Model Class Specification.116
9.2.1 Simple Variable Formal Model .116
9.2.2 Array Variable Formal Model.119
9.2.3 Record Variable Formal Model.121
9.2.4 Variable List Formal Model.122
9.3 Variable ASE Service Specification .123
9.3.1 Read Service.124
9.3.2 Read List Service .126
9.3.3 Write Service.129
9.3.4 Write List Service .131
9.3.5 Information Report Service .134
9.3.6 Information Report List Service.135
9.3.7 Exchange Service .137
9.3.8 Exchange List Service.141
10 EVENT ASE.146

10.1 Overview.146
10.2 Event Model Class Specifications .148
10.2.1 Event Formal Model.148
10.2.2 Event List Formal Model .153
10.2.3 Notifier Formal Model.154
10.3 Event ASE Service Specifications .156
10.3.1 Acknowledge Event.157
10.3.2 Acknowledge Event List Service.158
10.3.3 Enable Event Service.160
10.3.4 Event Notification Service .161
10.3.5 Enable Event List Service .163
10.3.6 Notification Recovery Service .165
10.3.7 Get Event Summary Service.166
10.3.8 Get Event Summary List Service .169
10.3.9 Query Event Summary List Service .172

61158-5 © IEC:1999 – 5 –
Clause Page
11 LOAD REGION ASE .176

11.1 Overview.176

11.2 Load Region Model Specification.176

11.2.1 Load Region Formal Model.177

11.3 Load Region Service Specification.181

11.3.1 Initiate Load Service .182

11.3.2 Terminate Load Service.183
11.3.3 Push Segment Service .185
11.3.4 Pull Segment Service.186

11.3.5 Discard Service.188

11.4 Load Region State Machines .189

11.4.1 Pull Upload State Machine.189

11.4.2 Pull Download State Machine .191
11.4.3 Push Download State Machine.194
12 FUNCTION INVOCATION ASE .198
12.1 Overview.198
12.2 Function Invocation Model Class Specifications .198
12.2.1 Function Invocation Class Definition.198
12.2.2 Action Class Definition.202
12.3 Function Invocation Model Service Specifications .204
12.3.1 Start Service .204
12.3.2 Stop Service.205
12.3.3 Resume Service.207
12.3.4 Reset Service.208
12.3.5 Kill Service .209
12.3.6 Action Invoke Service .210
12.3.7 Action Return Service .211
12.4 Function Invocation State Machine .213
ANNEX A — MODEL FOR SERVICE ERROR REPORTING .216
A.1 Introduction.216
A.2 Error Handling Procedure.217
ANNEX B — SUMMARY OF FAL CLASSES.219
ANNEX C — PERMITTED FAL SERVICES BY AREP ROLE .220
ANNEX D — QUEUED USER-TRIGGERED UNI-DIRECTIONAL (QUU) AR ENDPOINT FORMAL
MODEL.222
D.1 Description.222
D.2 Formal Class Definition .222
D.2.1 Network Management Attributes.222
D.2.2 Services .223

ANNEX E — QUEUED USER-TRIGGERED BI-DIRECTIONAL CONNECTION-ORIENTED (QUB-CO)
AR ENDPOINT FORMAL MODEL .224
E.1 Description.224
E.2 Formal Class Definition .225
E.2.1 Network Management Attributes.225
E.2.2 Services .226
ANNEX F — QUEUED USER-TRIGGERED BI-DIRECTIONAL CONNECTIONLESS (QUB-CL) AR
ENDPOINT FORMAL MODEL .227
F.1 Description.227
F.2 Formal Class Definition .228
F.2.1 Network Management Attributes.228
F.2.2 Services .229

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ANNEX G — QUEUED USER-TRIGGERED BI-DIRECTIONAL WITH FLOW CONTROL (QUB-FC) AR
ENDPOINT FORMAL MODEL.230

G.1 Description.230

G.2 Formal Class Definition.231

G.2.1 Network Management Attributes.232

G.2.2 Services.233

ANNEX H — QUEUED USER-TRIGGERED BI-DIRECTIONAL WITH SEGMENTATION(QUB-SEG) AR

ENDPOINT FORMAL MODEL.234

H.1 Description.234

H.2 Formal Class Definition.235

H.2.1 Network Management Attributes.235
H.2.2 Services.236

ANNEX I — BUFFERED USER-TRIGGERED BI-DIRECTIONAL (BUB) AR ENDPOINT FORMAL
MODEL.237
I.1 Description.237
I.2 Formal Class Definition.238
I.2.1 Network Management Attributes.238
I.2.2 Services.239
ANNEX J — BUFFERED NETWORK-SCHEDULED UNI-DIRECTIONAL (BNU) AR ENDPOINT
FORMAL MODEL .240
J.1 Description.240
J.2 Formal Class Definition.243
J.2.1 Network Management Attributes.243
J.2.2 Services.243
ANNEX K — BUFFERED NETWORK-SCHEDULED BI-DIRECTIONAL (BNB) AR ENDPOINT
FORMAL MODEL .245
K.1 Description.245
K.2 Formal Class Definition.246
K.2.1 Network Management Attributes.246
K.2.2 Services.247
ANNEX L — BUFFERED NETWORK-SCHEDULED AND UNSCHEDULED UNI-DIRECTIONAL
(BNU-MP) AR ENDPOINT FORMAL MODEL.248
L.1 Description.248
L.2 Formal Class Definition.251
L.2.1 Network Management Attributes.251
L.2.2 Services.251

61158-5 © IEC:1999 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
DIGITAL DATA COMMUNICATIONS FOR MEASUREMENT AND CONTROL –

FIELDBUS FOR USE IN INDUSTRIAL CONTROL SYSTEMS –

Part 5: Application Layer Service definition

FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising all
national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. Their preparation is entrusted to technical
committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory
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2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an international
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interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form of
standards, technical specifications, technical reports or guides and they are accepted by the National Committees
in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any divergence
between the IEC Standard and the corresponding national or regional standard shall be clearly indicated in the
latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this technical specification may be the subject of
patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
The main task of IEC technical committees is to prepare International Standards. In exceptional
circumstances, a technical committee may propose the publication of a technical specification
when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• The subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide whether

they can be transformed into International Standards.
IEC 61158-5, which is a technical specification, has been prepared by subcommittee 65C: Digital
communications, of IEC technical committee 65: Industrial-process measurement and control.
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
65C/199/FDIS 65C/207+207A/RVD
Full information on the voting for the approval of this technical specification can be found in the
report on voting indicated in the above table.

– 8 – 61158-5 © IEC:1999
This publication has been drafted in accordance with the ISO/IEC Directives, Part 3.

IEC 61158 consists of the following parts, under the general title Digital data communications for
measurement and control — Fieldbus for use in industrial control systems:

Part 1: Introductory guide (under preparation)

Part 2: Physical layer specification and service definition

Part 3: Data Link Service definition

Part 4: Data Link Protocol specification

Part 5: Application layer service definition

Part 6: Application layer protocol specification

Part 7: System management (under consideration)
Part 8: Conformance testing (under consideration)
Annexes C to L form an integral part of this technical specification.
Annexes A and B are for information only.
This publication will be reviewed by the committee responsible for its preparation before 2002.
Information relating to confirmation, amendment or revision of the publication is available from the
IEC web site.
A bilingual version of this technical specification may be issued at a later date.

61158-5 © IEC:1999 – 9 –
INTRODUCTION
This technical specification describes the Fieldbus Application Layer services intended to support the

information interchange and the interactions between application processes.

This set of application layer standards and technical specifications does not specify individual

implementations or products, nor does it constrain the implementations of Application entities and
interfaces within the industrial automation system.

This set of application layer standards and technical specifications does not contain test specifications
used to demonstrate compliance with IEC 61158-5 and IEC 61158-6.

– 10 – 61158-5 © IEC:1999
DIGITAL DATA COMMUNICATIONS FOR MEASUREMENT AND CONTROL –

FIELDBUS FOR USE IN INDUSTRIAL CONTROL SYSTEMS –

Part 5: Application Layer Service definition

1 Scope
The Fieldbus Application Layer (FAL) provides user programs with a means to access the Fieldbus

communication environment. In this respect, the FAL can be viewed as a “window between

corresponding application programs”.

The FAL is an Application Layer Communication Standard designed to support the conveyance of time-

critical and non-time-critical application requests and responses among devices in an automation
environment. The term “time-critical” is used to represent the presence of an application time-window,
within which one or more specified actions are required to be completed with some defined level of
certainty.
This technical specification specifies the structure and services of the IEC Fieldbus Application Layer
(FAL). It is specified in conformance with the OSI Basic Reference Model (ISO/IEC 7498) and the OSI
Application Layer Structure (ISO/IEC 9545).
FAL services and protocols are provided by FAL application-entities (AE) contained within the application
processes. The FAL AE is composed of a set of object-oriented Application Service Elements (ASEs)
and a Layer Management Entity (LME) that manages the AE. The ASEs provide communication services
that operate on a set of related application process object (APO) classes. One of the FAL ASEs is a
management ASE that provides a common set of services for the management of the instances of FAL
classes.
This part of IEC 61158 specifies interactions between remote applications in terms of
- an abstract model for defining application resources (objects) capable of being manipulated by
users via the use of FAL Services,
- the primitives (interactions between the FAL and the FAL user) associated with each FAL Service;
- the parameters associated with each primitive;
- the interrelationship between and the valid sequences of the primitives for each service.
Although these services specify, from the perspective of applications, how request and responses are
issued and delivered, they do not include a specification of what the requesting and responding
applications are to do with them. That is, the behavioral aspects of the applications are not specified; only
a definition of what requests and responses they can send/receive is specified. This permits greater
flexibility to the FAL users in standardizing such object behavior. In addition to these services, some
supporting services are also defined in this specification to provide access to the FA
...