EN 61158-5-8:2008

SLOVENSKI STANDARD
01-julij-2008
1DGRPHãþD
SIST EN 61158-5:2004
Industrijska komunikacijska omrežja - Specifikacije za procesno vodilo - 5-8. del:
Definicija opravil na aplikacijskem nivoju - Elementi tipa 8 (IEC 61158-5-8:2007)
Industrial communication networks - Fieldbus specifications - Part 5-8: Application layer
service definition - Type 8 elements
Industrielle Kommunikationsnetze - Feldbusse - Teil 5-8: Dienstfestlegungen des
Application Layer (Anwendungsschicht) - Typ 8-Elemente
Réseaux de communication industriels - Spécifications des bus de terrain - Partie 5-8:
Définition des services des couches d'application - Eléments de type 8
Ta slovenski standard je istoveten z: EN 61158-5-8:2008
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
35.100.70 Uporabniški sloj Application layer
35.110 Omreževanje Networking
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 61158-5-8
NORME EUROPÉENNE
March 2008
EUROPÄISCHE NORM
ICS 35.100.70; 25.040.40 Partially supersedes EN 61158-5:2004

English version
Industrial communication networks -
Fieldbus specifications -
Part 5-8: Application layer service definition -
Type 8 elements
(IEC 61158-5-8:2007)
Réseaux de communication industriels -  Industrielle Kommunikationsnetze -
Spécifications des bus de terrain - Feldbusse -
Partie 5-8: Définition des services Teil 5-8: Dienstfestlegungen
des couches d'application - des Application Layer
(Anwendungsschicht) -
Eléments de type 8
(CEI 61158-5-8:2007) Typ 8-Elemente
(IEC 61158-5-8:2007)
This European Standard was approved by CENELEC on 2008-02-01. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels

© 2008 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61158-5-8:2008 E
Foreword
The text of document 65C/475/FDIS, future edition 1 of IEC 61158-5-8, prepared by SC 65C, Industrial
networks, of IEC TC 65, Industrial-process measurement, control and automation, was submitted to the
IEC-CENELEC parallel vote and was approved by CENELEC as EN 61158-5-8 on 2008-02-01.
This and the other parts of the EN 61158-5 series supersede EN 61158-5:2004.
With respect to EN 61158-5:2004 the following changes were made:
– deletion of Type 6 fieldbus for lack of market relevance;
– addition of new fieldbus types;
– partition into multiple parts numbered 5-2, 5-3, …, 5-20.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
(dop) 2008-11-01
national standard or by endorsement
– latest date by which the national standards conflicting
(dow) 2011-02-01
with the EN have to be withdrawn
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
EN 61784 series. Use of the various protocol types in other combinations may require permission from their respective
intellectual-property-right holders.
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 61158-5-8:2007 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 61158-2 NOTE  Harmonized as EN 61158-2:2008 (not modified).
IEC 61158-3-8 NOTE  Harmonized as EN 61158-3-8:2008 (not modified).
IEC 61158-4-8 NOTE  Harmonized as EN 61158-4-8:2008 (not modified).
IEC 61158-6-8 NOTE  Harmonized as EN 61158-6-8:2008 (not modified).
IEC 61784-1 NOTE  Harmonized as EN 61784-1:2008 (not modified).
IEC 61784-2 NOTE  Harmonized as EN 61784-2:2008 (not modified).
__________
- 3 - EN 61158-5-8:2008
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

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.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year

1) 2)
IEC 60559 - Binary floating-point arithmetic for HD 592 S1 1991
microprocessor systems
1)
ISO/IEC 646 - Information technology - ISO 7-bit coded - -
character set for information interchange

1) 2)
ISO/IEC 7498-1 - Information technology - Open Systems EN ISO/IEC 7498-1 1995
Interconnection - Basic Reference Model:
The Basic Model
1)
ISO/IEC 7498-3 - Information technology - Open Systems - -
Interconnection - Basic Reference Model:
Naming and addressing
1)
ISO/IEC 8822 - Information technology - Open Systems - -
Interconnection - Presentation service
definition
1)
ISO/IEC 8824 - Information technology - Open Systems - -
Interconnection - Specification of Abstract
Syntax Notation One (ASN.1)
1)
ISO/IEC 9545 - Information technology - Open Systems - -
Interconnection - Application Layer structure

1)
ISO/IEC 10731 - Information technology - Open Systems - -
Interconnection - Basic reference model -
Conventions for the definition of OSI services

1)
Undated reference.
2)
Valid edition at date of issue.

IEC 61158-5-8
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 5-8: Application layer service definition – Type 8 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XD
ICS 35.100.70; 25.040.40 ISBN 2-8318-9456-5

– 2 – 61158-5-8 © IEC:2007(E)
CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope.7
1.1 Overview .7
1.2 Specifications.8
1.3 Conformance.8
2 Normative references .8
3 Terms and definitions .9
3.1 ISO/IEC 7498-1 terms .9
3.2 ISO/IEC 8822 terms .9
3.3 ISO/IEC 9545 terms .9
3.4 ISO/IEC 8824 terms .9
3.5 Fieldbus data-link layer terms.9
3.6 Fieldbus application layer specific definitions .10
3.7 Abbreviations and symbols.16
3.8 Conventions .16
4 Concepts .20
4.1 Overview .20
4.2 Architectural relationships .20
4.3 Fieldbus Application Layer structure.22
4.4 FAL naming and addressing .32
4.5 Architecture summary.33
4.6 FAL service procedures.33
4.7 Notional FAL service procedures [INFORMATIVE].33
4.8 Common FAL attributes.34
4.9 Common FAL service parameters.35
4.10 APDU size.36
5 Data type ASE.36
5.1 General .36
5.2 Formal definition of data type objects .38
5.3 FAL defined data types.38
5.4 Data type ASE service specification .42
6 Communication model specification.42
6.1 ASEs.42
6.2 ARs .85
6.3 Summary of FAL classes .91
6.4 Permitted FAL services by AREP role.91
Bibliography.93

Figure 1 – Relationship to the OSI basic reference model.20
Figure 2 – Architectural positioning of the Type 8 FAL .21
Figure 3 – Client/server interactions .23
Figure 4 – Push model interactions .24
Figure 5 – APOs services conveyed by the FAL.25
Figure 6 – Application entity structure.27

61158-5-8 © IEC:2007(E) – 3 –
Figure 7 – Example FAL ASEs.28
Figure 8 – FAL management of objects.29
Figure 9 – ASE service conveyance.30
Figure 10 – Defined and established AREPs.32
Figure 11 – FAL architectural components .33
Figure 12 – Data type class hierarchy example .36
Figure 13 – The AR ASE conveys APDUs between APs.58
Figure 14 – 1-to-1 AR establishment.65

Table 1 – Get attributes service parameters.43
Table 2 – Identify.50
Table 3 – Get status .51
Table 4 – Initiate.53
Table 5 – Terminate.55
Table 6 – Reject .57
Table 7 – Conveyance of service primitives by AREP role .59
Table 8 – Valid combinations of AREP roles involved in an AR .59
Table 9 – AR-unconfirmed send.63
Table 10 – AR-establish service.64
Table 11 – Valid combinations of AREP classes to be related.66
Table 12 – AR-abort .67
Table 13 – AR-Data-Send-Acknowledge service parameters.68
Table 14 – Read service parameters.73
Table 15 – Write service parameters.74
Table 16 – Information report service.75
Table 17 – Start service parameters .79
Table 18 – Stop service parameters.80
Table 19 – Resume service parameters .81
Table 20 – Reset service parameters.82
Table 21 – State transitions for a function invocation object.84
Table 22 – FAL class summary .91
Table 23 – Services by AREP role .92

– 4 – 61158-5-8 © IEC:2007(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 5-8: Application layer service definition – Type 8 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 61158-5-8 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 61158-5 subseries cancel and replace
IEC 61158-5:2003. This edition of this part constitutes a technical revision.
This edition of IEC 61158-5 includes the following significant changes from the previous
edition:
a) deletion of the former Type 6 fieldbus for lack of market relevance;
b) addition of new types of fieldbuses;
c) partition of part 5 of the third edition into multiple parts numbered -5-2, -5-3, …

61158-5-8 © IEC:2007(E) – 5 –
The text of this standard is based on the following documents:
FDIS Report on voting
65C/475/FDIS 65C/486/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.

– 6 – 61158-5-8 © IEC:2007(E)
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 service is provided by the application protocol making use of the services
available from the data-link or other immediately lower layer. This standard defines the
application service characteristics that fieldbus applications and/or system management may
exploit.
Throughout the set of fieldbus standards, the term “service” refers to the abstract capability
provided by one layer of the OSI Basic Reference Model to the layer immediately above.
Thus, the application layer service defined in this standard is a conceptual architectural
service, independent of administrative and implementation divisions.

61158-5-8 © IEC:2007(E) – 7 –
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 5-8: Application layer service definition – Type 8 elements

1 Scope
1.1 Overview
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 8 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 service provided by the Type 8
fieldbus application layer in terms of
a) an abstract model for defining application resources (objects) capable of being
manipulated by users via the use of the FAL service,
b) the primitive actions and events of the service;
c) the parameters associated with each primitive action and event, and the form which they
take; and
d) the interrelationship between these actions and events, and their valid sequences.
The purpose of this standard is to define the services provided to
1) the FAL user at the boundary between the user and the application layer of the fieldbus
reference model, and
2) Systems Management at the boundary between the application layer and Systems
Management of the fieldbus reference model.
This standard specifies the structure and services of the Type 8 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

– 8 – 61158-5-8 © IEC:2007(E)
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.
1.2 Specifications
The principal objective of this standard is to specify the characteristics of conceptual
application layer services suitable for time-critical communications, and thus supplement the
OSI Basic Reference Model in guiding the development of application layer protocols for time-
critical communications.
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 services
standardized as the various Types of IEC 61158, and the corresponding protocols
standardized in subparts of IEC 61158-6.
This specification may be used as the basis for formal application programming interfaces.
Nevertheless, it is not a formal programming interface, and any such interface will need to
address implementation issues not covered by this specification, including
a) the sizes and octet ordering of various multi-octet service parameters, and
b) the correlation of paired request and confirm, or indication and response, primitives.
1.3 Conformance
This standard does not specify individual implementations or products, nor does it constrain
the implementations of application layer entities within industrial automation systems.
There is no conformance of equipment to this application layer service definition standard.
Instead, conformance is achieved through implementation of conforming application layer
protocols that fulfill the Type 8 application layer services as defined in this standard.
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 60559, Binary Floating-point Arithmetic for Microprocessor Systems
ISO/IEC 646, Information technology – ISO 7–bit coded character set for information
interchange
ISO/IEC 7498–1, Information technology – Open Systems Interconnection – Basic Reference
Model – Part 1: The Basic Model
ISO/IEC 7498–3, Information technology – Open Systems Interconnection – Basic Reference
Model – Part 3: Naming and addressing
ISO/IEC 8822, Information technology – Open Systems Interconnection – Presentation
service definition
ISO/IEC 8824, Information Technology – Abstract Syntax notation One (ASN-1): Specification
of basic notation
ISO/IEC 9545, Information technology – Open Systems Interconnection – Application Layer
structure
61158-5-8 © IEC:2007(E) – 9 –
ISO/IEC 10731, Information technology – Open Systems Interconnection – Basic Reference
Model – Conventions for the definition of OSI services
3 Terms and definitions
For the purposes of this document, the following terms, definitions, symbols, abbreviations
and conventions apply.
3.1 ISO/IEC 7498-1 terms
This standard is partly based on the concepts developed in ISO/IEC 7498-1, and makes use
of the following terms defined therein:
a) application entity
b) application process
c) application protocol data unit
d) application process invocation
e) application transaction
f) real open system
g) transfer syntax
3.2 ISO/IEC 8822 terms
For the purposes of this document, the following terms as defined in ISO/IEC 8822 apply:
a) abstract syntax
b) presentation context
3.3 ISO/IEC 9545 terms
For the purposes of this document, the following terms as defined in ISO/IEC 9545 apply:
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
3.4 ISO/IEC 8824 terms
For the purposes of this document, the following terms as defined in ISO/IEC 8824 apply:
a) object identifier
b) type
3.5 Fieldbus data-link layer terms
For the purposes of this document, the following terms, as defined in IEC 61158-3-8 and
IEC 61158-4-8, apply.
a) DLCEP
– 10 – 61158-5-8 © IEC:2007(E)
b) DLSAP
c) link
d) node
3.6 Fieldbus application layer specific definitions
3.6.1
access protection
limitation of the usage of an application object to one client
3.6.2
allocate
take a resource from a common area and assign that resource for the exclusive use of a
specific entity
3.6.3
application
function or data structure for which data is consumed or produced
3.6.4
application layer interoperability
capability of application entities to perform coordinated and cooperative operations using the
services of the FAL
3.6.5
application objects
multiple object classes that manage and provide a run time exchange of messages across the
network and within the network device
3.6.6
application process
part of a distributed application on a network, which is located on one device and
unambiguously addressed
3.6.7
application process identifier
distinguishes multiple application processes used in a device
3.6.8
application process object
component of an application process that is identifiable and accessible through an FAL
application relationship
NOTE  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.
3.6.9
application process object class
a class of application process objects defined in terms of the set of their network-accessible
attributes and services
3.6.10
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

61158-5-8 © IEC:2007(E) – 11 –
either by the exchange of application-protocol-data-units or as a result of preconfiguration
activities
3.6.11
application relationship application service element
application-service-element that provides the exclusive means for establishing and
terminating all application relationships
3.6.12
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
NOTE  Each application process involved in the application relationship maintains its own application relationship
endpoint.
3.6.13
attribute
description of an externally visible characteristic or feature of an object
NOTE  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.
3.6.14
behaviour
indication of how an object responds to particular eventss
3.6.15
class
a set of objects, all of which represent the same kind of system component
NOTE  A class is a generalisation of an 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.
3.6.16
class attribute
attribute that is shared by all objects within the same class
3.6.17
class code
unique identifier assigned to each object class
3.6.18
class specific service
service defined by a particular object class to perform a required function which is not
performed by a common service
NOTE  A class specific object is unique to the object class which defines it.
3.6.19
client
a) object which uses the services of another (server) object to perform a task
b) initiator of a message to which a server reacts
3.6.20
control commands
action invocations transferred from client to server to clear outputs, freeze inputs and/or
synchronise outputs
– 12 – 61158-5-8 © IEC:2007(E)
3.6.21
conveyance path
unidirectional flow of APDUs across an application relationship
3.6.22
cyclic
repetitive in a regular manner
3.6.23
data consistency
means for coherent transmission and access of the input- or output-data object between and
within client and server
3.6.24
dedicated AR
AR used directly by the FAL User
NOTE  On Dedicated ARs, only the FAL Header and the user data are transferred.
3.6.25
device
physical hardware connected to the link
NOTE  A device may contain more than one node.
3.6.26
dynamic AR
AR that requires the use of the AR establishment procedures to place it into an established
state
3.6.27
end node
producing or consuming node
3.6.28
endpoint
one of the communicating entities involved in a connection
3.6.29
engineering
abstract term that characterizes the client application or device responsible for configuring an
automation system via interconnecting data items
3.6.30
error
discrepancy between a computed, observed or measured value or condition and the specified
or theoretically correct value or condition
3.6.31
error class
general grouping for related error definitions and corresponding error codes
3.6.32
error code
identification of a specific type of error within an error class
3.6.33
event
an instance of a change of conditions

61158-5-8 © IEC:2007(E) – 13 –
3.6.34
group
(a) collection of objects
(b) address that identifies more than one entity
3.6.35
interface
a) shared boundary between two functional units, defined by functional characteristics, signal
characteristics, or other characteristics as appropriate
b) collection of FAL class attributes and services that represents a specific view on the FAL
class
3.6.36
invocation
act of using a service or other resource of an application process
NOTE  Each invocation represents a separate thread of control that may be described by its context. Once the
service completes, or use of the resource is released, the invocation ceases to exist. For service invocations, a
service that has been initiated but not yet completed is referred to as an outstanding service invocation.
3.6.37
index
address of an object within an application process
3.6.38
instance
the actual physical occurrence of an object within a class that identifies one of many objects
within the same object class
NOTE  The terms object, instance, and object instance are used to refer to a specific instance.
3.6.39
instance attributes
attribute that is unique to an object instance and not shared by the object class
3.6.40
instantiated
object that has been created in a device
3.6.41
manufacturer ID
identification of each product manufacturer by a unique number
3.6.42
management information
network-accessible information that supports managing the operation of the fieldbus system,
including the application layer
NOTE  Managing includes functions such as controlling, monitoring, and diagnosing.
3.6.43
member
piece of an attribute that is structured as an element of an array
3.6.44
method
a synonym for an operational service which is provided by the server ASE and
invoked by a client
– 14 – 61158-5-8 © IEC:2007(E)
3.6.45
network
a set of nodes connected by some type of communication medium, including any intervening
repeaters, bridges, routers and lower-layer gateways
3.6.46
object
abstract representation of a particular component within a device, usually a collection of
related data (in the form of variables) and methods (procedures) for operating on that data
that have clearly defined interface and behaviour
3.6.47
object specific service
service unique to the object class which defines it
3.6.48
peer
role of an AR endpoint in which it is capable of acting as both client and server
3.6.49
point-to-point connection
connection that exists between exactly two application objects
3.6.50
pre-defined AR endpoint
AR endpoint that is defined locally within a device without use of the create service
NOTE  Pre-defined ARs that are not pre-established are established before being used
3.6.51
pre-established AR endpoint
AR endpoint that is placed in an established state during configuration of the AEs that control
its endpoints
3.6.52
property
descriptive information about an object
3.6.53
provider
source of a data connection
3.6.54
publisher
role of an AR endpoint that transmits APDUs onto the fieldbus for consumption by one or
more subscribers
NOTE  A publisher may not be aware of the identity or the number of subscribers and it may publish its APDUs
using a dedicated AR.
3.6.55
push publisher
type of publisher that publishes an object in an unconfirmed service request APDU
3.6.56
push subscriber
type of subscriber that recognizes received unconfirmed service request APDUs as published
object data
61158-5-8 © IEC:2007(E) – 15 –
3.6.57
resource
a processing or information capability of a subsystem
3.6.58
server
a) role of an AREP in which it returns a confirmed service response APDU to the client that
initiated the request
b) object which provides services to another (client) object
3.6.59
service
operation or function than an object and/or object class performs upon request from another
object and/or object class
3.6.60
subscriber
role of an AREP in which it receives APDUs produced by a publisher

– 16 – 61158-5-8 © IEC:2007(E)
3.7 Abbreviations and symbols
AE Application entity
AL Application layer
ALME Application layer management entity
ALP Application layer protocol
APO Application object
AP Application process
APDU Application protocol data unit
API Application process identifier
AR Application relationship
AREP Application relationship endpoint
ASE Application service element
CIM Computer integrated manufacturing
Cnf Confirmation
CR Communication relationship
CREP Communication relationship endpoint
DL- (as a prefix) Data-link-
DLC Data-link connection
DLCEP Data-link connection endpoint
DLL Data-link layer
DLM Data-link-management
DLSAP Data-link service access point
FAL Fieldbus application layer
FIFO First in first out
ID Identifier
Ind Indication
LME Layer management entity
OSI Open Systems Interconnect
PDU Protocol data unit
Req Request
Rsp Response
SAP Service access point
3.8 Conventions
3.8.1 Overview
The FAL is defined as a set of object-oriented ASEs. Each ASE is specified in a separate
subclause. Each ASE specification is composed of two parts, its class specification, and its
service specification.
The class specification defines the attributes of the class. The attributes are accessible from
instances of the class using the Object Management ASE services specified in Clause 5 of
this standard. The service specification defines the services that are provided by the ASE.

61158-5-8 © IEC:2007(E) – 17 –
3.8.2 General conventions
This standard uses the descriptive conventions given in ISO/IEC 10731.
3.8.3 Conventions for class definitions
Class definitions are described using templates. Each template consists of a list of attributes
for the class. The general form of the template is shown below:
FAL ASE: ASE Name
CLASS:  Class Name
CLASS ID: #
PARENT CLASS: Parent Class Name
ATTRIBUTES:
1 (o) Key Attribute: numeric identifier
2 (o) Key Attribute: name
3 (m) Attribute: attribute name(values)
4 (m) Attribute: attribute name(values)
4.1 (s) Attribute: attribute name(values)
4.2 (s) Attribute: attribute name(values)
4.3 (s) Attribute: attribute name(values)
5. (c) Constraint: constraint expression
5.1 (m) Attribute: attribute name(values)
5.2 (o) Attribute: attribute name(values)
6 (m) Attribute: attribute name(values)
6.1 (s) Attribute: attribute name(values)
6.2 (s) Attribute: attribute name(values)
SERVICES:
1 (o) OpsService: service name
2. (c) Constraint: constraint expression
2.1 (o) OpsService: service name
3 (m) MgtService: service name
(1) The "FAL ASE:" entry is the name of the FAL ASE that provides the services for the class
being specified.
(2) The "CLASS:" entry is the name of the class being specified. All objects defined using
this template will be an instance of this class. The class may be specified by this
standard, or by a user of this standard.
(3) The "CLASS ID:" entry is a number that identifies the class being specified. This number
is unique w
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