IEC 61158-6-5:2007

IEC 61158-6-5
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-5: Application layer protocol specification – Type 5 elements

All rights reserved. Unless otherwise specified, 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
either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

IEC Central Office
3, rue de Varembé
CH-1211 Geneva 20
Switzerland
Email: inmail@iec.ch
Web: www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
ƒ Catalogue of IEC publications: www.iec.ch/searchpub
The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,…).
It also gives information on projects, withdrawn and replaced publications.
ƒ IEC Just Published: www.iec.ch/online_news/justpub
Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available
on-line and also by email.
ƒ Electropedia: www.electropedia.org
The world's leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions
in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical
Vocabulary online.
ƒ Customer Service Centre: www.iec.ch/webstore/custserv
If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service
Centre FAQ or contact us:
Email: csc@iec.ch
Tel.: +41 22 919 02 11
Fax: +41 22 919 03 00
IEC 61158-6-5
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-5: Application layer protocol specification – Type 5 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XE
ICS 35.100.70; 25.040.40 ISBN 2-8318-9477-8

– 2 – 61158-6-5 © IEC:2007(E)
CONTENTS
FOREWORD.7
INTRODUCTION.9
1 Scope.10
1.1 General .10
1.2 Specifications.11
1.3 Conformance.11
2 Normative references .11
3 Terms, definitions, symbols, abbreviations and conventions .11
3.1 Terms and definitions from other ISO/IEC standards .11
3.2 IEC/TR 61158-1 terms.12
3.3 Abbreviations and symbols.16
3.4 Conventions .17
3.5 Conventions used in state machines .17
4 Protocol.19
4.1 Overview .19
4.2 FAL syntax description .19
4.3 Transfer syntax .19
4.4 FAL protocol state machine structure .75
4.5 SMK state machine .75
4.6 VCR state machine.92
4.7 FAL service protocol machine (FSPM).93
4.8 Application relationship protocol machines (ARPMs) .93
4.9 DLL mapping protocol machine (DMPM).108
Bibliography.114

Figure 1 – State transition diagram for SMK.77
Figure 2 – State transition diagram of client / server ARPM .97
Figure 3 – State transition diagram of the publisher / subscriber ARPM . 104
Figure 4 – State transition diagram of DMPM.110

Table 1 – Conventions used for state machines .17
Table 2 – Data types.20
Table 3 – Data types.20
Table 4 – APDU header format .21
Table 5 – FDA address use.22
Table 6 – FDA address header field APDUs sent by a client VCR endpoint.23
Table 7 – FDA address header field APDUs sent by a server VCR endpoint .24
Table 8 – FDA address header field APDUs sent by a publisher VCR endpoint.24
Table 9 – FDA address header field APDUs sent by a report source VCR endpoint .25
Table 10 – APDU trailer fields.25
Table 11 – Request APDU parameters.27
Table 12 – SMK FDA address values.29
Table 13 – SMK FDA address values.30

61158-6-5 © IEC:2007(E) – 3 –
Table 14 – Request APDU parameters.31
Table 15 – SMK FDA address values for SM identify .32
Table 16 – SMK FDA address values for SMK set assignment info request APDUs .32
Table 17 – SMK clear address request APDU parameters.33
Table 18 – SMK FDA address values for SMK set assignment info request APDUs .33
Table 19 – SMK set assignment info request APDU parameters .34
Table 20 – SMK set assignment info response APDU parameters.35
Table 21 – SMK FDA address values for SMK device clear assignment Info APDUs .36
Table 22 – SMK clear assignment info request APDU parameters .36
Table 23 – SMK FDA address values for SMK device annunciation request APDUs.36
Table 24 – SMK device annunciation request APDU parameters.37
Table 25 – Initiate request APDU parameters .40
Table 26 – Initiate response APDU parameters.40
Table 27 – Abort request APDU parameters .40
Table 28 – Get response APDU parameters.41
Table 29 – Identify response APDU parameters.41
Table 30 – Get OD request APDU parameters .41
Table 31 – Get OD response APDU parameters.42
Table 32 – Initiate put OD request APDU parameters .42
Table 33 – Put OD request APDU parameters.42
Table 34 – Generic initiate download sequence request APDU parameters.43
Table 35 – Generic download segment request APDU parameters.44
Table 36 – Generic terminate download sequence request APDU parameters .44
Table 37 – Response APDU parameters .44
Table 38 – Initiate download sequence request APDU parameters.45
Table 39 – Download segment request APDU parameters .45
Table 40 – Download segment response APDU parameters.45
Table 41 – Terminate download sequence request APDU parameters .46
Table 42 – Initiate upload sequence request APDU parameters .46
Table 43 – Upload segment request APDU parameters.47
Table 44 – Upload segment response APDU parameters .47
Table 45 – Terminate upload sequence request APDU parameters .47
Table 46 – Request domain download request APDU parameters .48
Table 47 – Request domain upload request APDU parameters .48
Table 48 – Create program invocation request APDU parameters.49
Table 49 – Create program invocation response APDU parameters .49
Table 50 – Delete program invocation request APDU parameters .49
Table 51 – Start request APDU parameters .50
Table 52 – Stop request APDU parameters.50
Table 53 – Resume request APDU parameters .50
Table 54 – Reset request APDU parameters.51
Table 55 – Kill request APDU parameters .51
Table 56 – Read request APDU parameters.51

– 4 – 61158-6-5 © IEC:2007(E)
Table 57 – Read response APDU parameters .52
Table 58 – Read with subindex request APDU parameters.52
Table 59 – Read with subindex response APDU parameters .52
Table 60 – Write request APDU parameters.52
Table 61 – Write with subindex request APDU parameters.53
Table 62 – Define variable list request APDU parameters .53
Table 63 – Define variable list response APDU parameters .53
Table 64 – Delete variable list request APDU parameters .54
Table 65 – Information report request APDU parameters .54
Table 66 – Information report with subindex request APDU parameters .54
Table 67 – Information report on change request APDU parameters .55
Table 68 – Information report on change with subindex request APDU parameters .55
Table 69 – Event notification request APDU parameters .55
Table 70 – Alter event condition monitoring request APDU parameters.56
Table 71 – Acknowledge event notification request APDU parameters .56
Table 72 – LAN redundancy diagnostic message request APDU parameters .57
Table 73 – LAN redundancy get information response APDU parameters .59
Table 74 – LAN redundancy get statistics request APDU parameters.61
Table 75 – Object description header.63
Table 76 – Null object .63
Table 77 – Structure of the list of object descriptions .64
Table 78 – Structure of a load region in the S-OD.65
Table 79 – Structure of a function invocation in the DP-OD.66
Table 80 – Structure of an event in the S-OD.67
Table 81 – Structure of a data type in the ST-OD.67
Table 82 – Structure of a data type structure description in the ST-OD .68
Table 83 – Structure of a simple variable in the S-OD.68
Table 84 – Structure of an array in the S-OD .69
Table 85 – Structure of a record in the S-OD .70
Table 86 – Structure of a variable list in the DV-OD .71
Table 87 – Common error parameters.72
Table 88 – PI error parameters .72
Table 89 – OD error parameters .72
Table 90 – Error class and error code values .73
Table 91 – SMKPM service primitives .76
Table 92 – SMKPM states.77
Table 93 – SMKPM state table – initialization .78
Table 94 – SMKPM state table – receive transitions.78
Table 95 – SMKPM state table – internal events .83
Table 96 – HseRepeatTimerExpires () .84
Table 97 – RcvNewNetworkAddress (interface, address) .84
Table 98 – RcvMsg ().84
Table 99 – SntpSyncLost ().84

61158-6-5 © IEC:2007(E) – 5 –
Table 100 – AddressToClear (sm_svc) .85
Table 101 – AssignmentInfo_Set () .85
Table 102 – ConfigurationSessionActive () .85
Table 103 – DeviceRedundancyState () .85
Table 104 – DevId_Match (sm_svc) .86
Table 105 – DuplicateQueryIdMatch (sm_svc) .86
Table 106 – DuplicatePdTagDetected ().86
Table 107 – FdaAddressType (sm_svc) .86
Table 108 – IsValid (sm_svc).87
Table 109 – NetworkAddressChange (interface, address) .87
Table 110 – NumberOfAssignedAddresses ().87
Table 111 – OperationalRestore () .87
Table 112 – PdTag_Match (sm_svc) .87
Table 113 – PdTagDeviceIndex_Check (sm_svc).88
Table 114 – Query_Match (sm_svc).88
Table 115 – QueryType (sm_svc) .88
Table 116 – SmCacheEntry (sm_svc) .88
Table 117 – Clear_Address (interface_to_clear) .89
Table 118 – Clear_DuplicatePdTagFlag () .89
Table 119 – Get_AddlCode () .89
Table 120 – New_Address (interface, address).89
Table 121 – Restart_HseRepeatTimer ().90
Table 122 – Restore_Defaults () .90
Table 123 – Send_SM_CommonErrorRsp (sm_service_type, svc_spec_params).90
Table 124 – Send_SM_ReqRspMessage (sm_svc) .90
Table 125 – Set_Assignment_Data (sm_svc) .90
Table 126 – Set_DuplicatePdTagFlag ().91
Table 127 – SvcType (sm_svc) .91
Table 128 – Additional code used by error class and code.91
Table 129 – Additional code parameter IDs.92
Table 130 – Primitives issued by FSPM to ARPM .94
Table 131 – Primitives issued by ARPM to FSPM .94
Table 132 – Parameters used with primitives exchanged between FSPM and ARPM .95
Table 133 – Client / Server ARPM states .97
Table 134 – Client / server ARPM state table – sender transitions .98
Table 135 – Client / server ARPM state table – receiver transitions .99
Table 136 – Primitives issued by FSPM to ARPM .101
Table 137 – Primitives issued by ARPM to FSPM .102
Table 138 – Parameters used with primitives exchanged between FSPM and ARPM . 102
Table 139 – Publisher / subscriber ARPM states.103
Table 140 – MulticastARPM state table – sender transitions . 104
Table 141 – MulticastARPM state table – receiver transitions . 105
Table 142 – BuildFAL-ErrPDU() .105

– 6 – 61158-6-5 © IEC:2007(E)
Table 143 – BuildFAL-ReqRspPDU() .106
Table 144 – GetArepId() .106
Table 145 – ConfigurationArCheckOK() .106
Table 146 – FAL_Pdu_BufferSize().106
Table 147 – FAL_Pdu_Confirmed() .106
Table 148 – FAL_Pdu_DuplicateMsg () .106
Table 149 – FAL_Pdu_GetVcrId() .107
Table 150 – FAL_Pdu_InactivityCloseTime().107
Table 151 – FAL_Pdu_TransmitDelayTime() .107
Table 152 – FAL_Pdu_SvcType() .107
Table 153 – FAL_Pdu_RemoteAddress() .107
Table 154 – FAL_Pdu_TrailerFields().107
Table 155 – FAL_Pdu_ServiceSpecificParameters() .108
Table 156 – FAL_Pdu_Valid() .108
Table 157 – MaxOutstandingReached() .108
Table 158 – StartInactivityCloseTimer() .108
Table 159 – Primitives issued by ARPM to DMPM .109
Table 160 – Primitives issued by DMPM to ARPM .109
Table 161 – Parameters used with primitives exchanged between ARPM and DMPM . 109
Table 162 – Primitives exchanged between the socket model and DMPM . 109
Table 163 – Parameters of DMPM/socket model primitives . 110
Table 164 – DMPM state descriptions.110
Table 165 – DMPM state table – sender transitions . 111
Table 166 – DMPM state table – receiver transitions . 112
Table 167 – ConnectionOriented.112
Table 168 – GetBufferedData .112
Table 169 – GetConnectionId .112
Table 170 – LoadBuffer .113
Table 171 – RemainingBufferSizeCheck .113
Table 172 – StartTransmitDelayTimer.113

61158-6-5 © IEC:2007(E) – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 6–5: Application layer protocol specification – Type 5 elements

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of 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, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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.
NOTE  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 particular data-link layer protocol type to be used with physical layer and application layer protocols in Type
combinations as specified explicitly in the IEC 61784 series. Use of the various protocol types in other
combinations may require permission from their respective intellectual-property-right holders.
International standard IEC 61158-6-5 has been prepared by subcommittee 65C: Industrial
networks, of IEC technical committee 65: Industrial-process measurement, control and
automation.
This first edition and its companion parts of the IEC 61158-6 subseries cancel and replace
IEC 61158-6:2003. This edition of this part constitutes an editorial revision.
This edition of IEC 61158-6 includes the following significant changes from the previous
edition:
a) deletion of the former Type 6 fieldbus for lack of market relevance;

– 8 – 61158-6-5 © IEC:2007(E)
b) addition of new types of fieldbuses;
c) partition of part 6 of the third edition into multiple parts numbered -6-2, -6-3, …
The text of this standard is based on the following documents:
FDIS Report on voting
65C/476/FDIS 65C/487/RVD
Full information on the voting for the approval of this 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.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under http://webstore.iec.ch in the
data related to the specific publication. At this date, the publication will be:
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
NOTE  The revision of this standard will be synchronized with the other parts of the IEC 61158 series.
The list of all the parts of the IEC 61158 series, under the general title Industrial
communication networks – Fieldbus specifications, can be found on the IEC web site.

61158-6-5 © IEC:2007(E) – 9 –
INTRODUCTION
This part of IEC 61158 is one of a series produced to facilitate the interconnection of
automation system components. It is related to other standards in the set as defined by the
“three-layer” fieldbus reference model described in IEC/TR 61158-1.
The application protocol provides the application service by making use of the services
available from the data-link or other immediately lower layer. The primary aim of this standard
is to provide a set of rules for communication expressed in terms of the procedures to be
carried out by peer application entities (AEs) at the time of communication. These rules for
communication are intended to provide a sound basis for development in order to serve a
variety of purposes:
• as a guide for implementors and designers;
• for use in the testing and procurement of equipment;
• as part of an agreement for the admittance of systems into the open systems environment;
• as a refinement to the understanding of time-critical communications within OSI.
This standard is concerned, in particular, with the communication and interworking of sensors,
effectors and other automation devices. By using this standard together with other standards
positioned within the OSI or fieldbus reference models, otherwise incompatible systems may
work together in any combination.

– 10 – 61158-6-5 © IEC:2007(E)
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 6-5: Application layer protocol specification – Type 5 elements

1 Scope
1.1 General
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.”
This standard 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 5 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.
This standard defines in an abstract way the externally visible behavior provided by the Type
5 fieldbus Application Layer in terms of
a) the abstract syntax defining the application layer protocol data units conveyed between
communicating application entities,
b) the transfer syntax defining the application layer protocol data units conveyed between
communicating application entities,
c) the application context state machine defining the application service behavior visible
between communicating application entities; and
d) the application relationship state machines defining the communication behavior visible
between communicating application entities; and.
The purpose of this standard is to define the protocol provided to
1) define the wire-representation of the service primitives defined in IEC 61158-5-5, and
2) define the externally visible behavior associated with their transfer.
This standard specifies the protocol of the Type 5 IEC fieldbus Application Layer, 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.
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 standard to provide access to the FAL to control certain aspects of its operation.

61158-6-5 © IEC:2007(E) – 11 –
1.2 Specifications
The principal objective of this standard is to specify the syntax and behavior of the application
layer protocol that conveys the application layer services defined in IEC 61158-5-5.
A secondary objective is to provide migration paths from previously-existing industrial
communications protocols. It is this latter objective which gives rise to the diversity of
protocols standardized in IEC 61158-6.
1.3 Conformance
This standard-6 does not specify individual implementations or products, nor does it constrain
the implementations of application layer entities within industrial automation systems.
Conformance is achieved through implementation of this application layer protocol
specification.
2 Normative references
The following referenced documents are indispensable for the application 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.
IEC 61158-3-1, Industrial communication networks – Fieldbus specifications – Part 3-1: Data-
link layer service definition – Type 1 elements
IEC 61158-4-1, Industrial communication networks – Fieldbus specifications – Part 4-1: Data-
link layer protocol specification – Type 1 elements
IEC 61158-5-5, Industrial communication networks – Fieldbus specifications – Part 5-5:
Application layer service definition – Type 5 elements
ISO/IEC 9545, Information technology – Open Systems Interconnection – Application Layer
structure
ISO/IEC 7498-1, Information technology – Open Systems Interconnection – Basic Reference
Model — Part 1: The Basic Model
ISO/IEC 8824, Information technology – Open Systems Interconnection – Specification of
Abstract Syntax Notation One (ASN.1)
ISO/IEC 8825, Information technology – ASN.1 encoding rules: Specification of Basic
Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules
(DER)
3 Terms, definitions, symbols, abbreviations and conventions
For the purposes of this document, the following definitions apply.
3.1 Terms and definitions from other ISO/IEC standards
3.1.1 Terms and definitions from ISO/IEC 7498-1
a) abstract syntax
b) application entity
c) application process
d) application protocol data unit
e) application service element

– 12 – 61158-6-5 © IEC:2007(E)
f) application entity invocation
g) application process invocation
h) application transaction
i) presentation context
j) real open system
k) transfer syntax
3.1.2 Terms and definitions from ISO/IEC 9545
a) application-association
b) application-context
c) application context name
d) application-entity-invocation
e) application-entity-type
f) application-process-invocation
g) application-process-type
h) application-service-element
i) application control service element
3.1.3 Terms and definitions from ISO/IEC 8824
a) object identifier
b) type
c) value
d) simple type
e) structured type
f) component type
g) tag
h) Boolean type
i) true
j) false
k) integer type
l) bitstring type
m) octetstring type
n) null type
o) sequence type
p) sequence of type
q) choice type
r) tagged type
s) any type
t) module
u) production
3.1.4 Terms and definitions from ISO/IEC 8825
a) encoding (of a data value)
b) data value
c) identifier octets (the singular form is used in this standard)
d) length octet(s) (both singular and plural forms are used in this standard)
e) contents octets
3.2 IEC/TR 61158-1 terms
The following IEC/TR 61158-1 terms apply.
3.2.1 application
function or data structure for which data is consumed or produced
3.2.2 application layer interoperability
capability of application entities to perform coordinated and cooperative operations using the
services of the FAL
61158-6-5 © IEC:2007(E) – 13 –
3.2.3 application object
object class that manages and provides the run time exchange of messages across the
network and within the network device
NOTE: Multiple types of application object classes may be defined
3.2.4 application process
part of a distributed application on a network, which is located on one device and
unambiguously addressed
3.2.5 application process identifier
distinguishes multiple application processes used in a device
3.2.6 application process object
component of an application process that is identifiable and accessible through an FAL
application relationship. Application process object definitions are composed of a set of
values for the attributes of their class (see the definition for Application Process Object Class
Definition). Application process object definitions may be accessed remotely using the
services of the FAL Object Management ASE. FAL Object Management services can be used
to load or update object definitions, to read object definitions, and to dynamically create and
delete application objects and their corresponding definitions
3.2.7 application process object class
a class of application process objects defined in terms of the set of their network-accessible
attributes and services
3.2.8 application relationship
cooperative association between two or more application-entity-invocations for the purpose of
exchange of information and coordination of their joint operation. This relationship is activated
either by the exchange of application-protocol-data-units or as a result of preconfiguration
activities
3.2.9 application relationship application service element
application-service-element that provides the exclusive means for establishing and
terminating all application relationships
3.2.10 application relationship endpoint
context and behavior of an application relationship as seen and maintained by one of the
application processes involved in the application relationship. Each application process
involved in the application relationship maintains its own application relationship endpoint
3.2.11 attribute
description of an externally visible characteristic or feature of an object. The attributes of an
object contain information about variable portions of an object. Typically, they provide status
information or govern the operation of an object. Attributes may also affect the behaviour of
an object. Attributes are divided into class attributes and instance attributes
3.2.12 behaviour
indication of how the object responds to particular events. Its description includes the
relationship between attribute values and services

– 14 – 61158-6-5 © IEC:2007(E)
3.2.13 class
a set of objects, all of which represent the same kind of system component. A class is a
generalisation of the object; a template for defining variables and methods. All objects in a
class are identical in form and behaviour, but usually contain different data in their attributes
3.2.14 class attributes
an attribute that is shared by all objects within the same class
3.2.15 class code
a unique identifier assigned to each object class
3.2.16 class specific service
a service defined by a particular object class to perform a required function which is not
performed by a common service. A class specific object is unique to the object class which
defines it
3.2.17 client
(a) an object which uses the services of another (server) object to perform a task
(b) an initiator of a message to which a server reacts, such as the role of an AR endpoint in
which it issues confirmed service request APDUs to a single AR endpoint acting as a server
3.2.18 conveyance path
unidirectional flow of APDUs across an application relationship
3.2.19 cyclic
term used to describe events which repeat in a regular and repetitive manner
3.2.20 dedicated AR
AR used directly by the FAL User. On Dedicated ARs, only the FAL Header and the user data
are transferred
3.2.21 device
a physical hardwar
...