IEC 61158-6-18:2007

IEC 61158-6-18
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-18: Application layer protocol specification – Type 18 elements

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IEC 61158-6-18
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-18: Application layer protocol specification – Type 18 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XB
ICS 35.100.70; 25.040.40 ISBN 2-8318-9496-4

– 2 – 61158-6-18 © IEC:2007(E)

CONTENTS
FOREWORD.5

INTRODUCTION.7

1 Scope.8

1.1 General .8

1.2 Specifications.8

1.3 Conformance.8

2 Normative references .9

3 Terms and definitions .9
3.1 Terms and definitions from other ISO/IEC standards .9
3.2 Other terms and definitions .10
3.3 .Abbreviations and symbols.19
3.4 Additional abbreviations and symbols for decentralized periphery .19
3.5 Conventions .21
4 Abstract syntax.21
4.1 M1 device manager PDU abstract syntax .21
4.2 M2 device manager PDU abstract syntax .21
4.3 S1 device manager PDU abstract syntax.22
4.4 S2 device manager PDU abstract syntax.22
4.5 M1 connection manager PDU abstract syntax.22
4.6 M2 connection manager PDU abstract syntax.23
4.7 S1 connection manager PDU abstract syntax .24
4.8 S2 connection manager PDU abstract syntax .24
4.9 M1 cyclic transmission PDU abstract syntax.24
4.10 M2 cyclic transmission PDU abstract syntax.25
4.11 S1 cyclic transmission PDU abstract syntax .25
4.12 S2 cyclic transmission PDU abstract syntax .26
5 Transfer syntax .26
5.1 M1 device manager PDU encoding.26
5.2 M2 device manager PDU encoding.28
5.3 S1 device manager PDU encoding .29
5.4 S2 device manager PDU encoding .30
5.5 M1 connection manager PDU encoding .31

5.6 M2 connection manager PDU encoding .35
5.7 S1 connection manager PDU encoding.35
5.8 S2 connection manager PDU encoding.36
5.9 M1 cyclic transmission PDU encoding .37
5.10 M2 cyclic transmission PDU encoding .38
5.11 S1 cyclic transmission PDU encoding.39
5.12 S2 cyclic transmission PDU encoding.41
5.13 Acyclic transmission PDU encoding.42
6 Structure of FAL protocol state machines .50
7 AP-context state machine.51
8 FAL service protocol machine (FSPM).51
8.1 Overview .51
8.2 FAL service primitives .51
9 AR protocol machine (ARPM) .52

61158-6-18 © IEC:2007(E) – 3 –

9.1 Overview .52

9.2 M1 master ARPM .52

9.3 M2 master ARPM .57

9.4 Slave ARPM.60

10 DLL mapping protocol machine (DMPM).63

10.1 Overview .63

10.2 Primitives received from the ARPM .63

10.3 Indications received from the DL .63

Bibliography.64

Figure 1 – Parameter block 1 command parameter field.44
Figure 2 – Parameter block 2 command parameter field.45
Figure 3 – Relationships among protocol machines and adjacent layers .50
Figure 4 – ARPM M1 master AR state diagram .53
Figure 5 – ARPM M2 master AR state diagram .57
Figure 6 – ARPM slave AR state diagram .60

Table 1 – M1 device manager attribute format .21
Table 2 – M2 device manager attribute format .22
Table 3 – S1 device manager attribute format.22
Table 4 – S2 device manager attribute format.22
Table 5 – M1 connection manager attribute format.23
Table 6 – M2 connection manager attribute format.24
Table 7 – S1 connection manager attribute format .24
Table 8 – S2 connection manager attribute format .24
Table 9 – M1 cyclic transmission attribute format.25
Table 10 – M2 cyclic transmission attribute format.25
Table 11 – S1 cyclic transmission attribute format .25
Table 12 – S2 cyclic transmission attribute format .26
Table 13 – M1 device manager attribute encoding .27
Table 14 – M2 device manager attribute encoding .29
Table 15 – S1 device manager attribute encoding.30

Table 16 – S2 device manager attribute encoding.31
Table 17 – M1 connection manager attribute encoding .32
Table 18 – M2 connection manager attribute encoding .35
Table 19 – S1 connection manager attribute encoding .36
Table 20 – S2 connection manager attribute encoding .36
Table 21 – M1 cyclic transmission attribute encoding.37
Table 22 – M2 cyclic transmission attribute encoding.39
Table 23 – S1 cyclic transmission attribute encoding .40
Table 24 – S2 cyclic transmission attribute encoding .41
Table 25 – Acyclic transmission – message data encoding .42
Table 26 – Command header format .43
Table 27 – Command codes .43

– 4 – 61158-6-18 © IEC:2007(E)

Table 28 – System information command parameter field .46

Table 29 – System information command parameter field .46

Table 30 – System information command parameter field .46

Table 31 – System information command parameter field .47

Table 32 – Line test command parameter field.47

Table 33 – Memory read command parameter field.48

Table 34 – Memory write command parameter field .49

Table 35 – FSPM events.52

Table 36 – M1 master state-event table 1 – events .55
Table 37 – M1 master state-event table 2 – receipt of FSPM service primitives .55
Table 38 – M1 master state-event table 3 – receipt of DMPM service primitives.57
Table 39 – M2 master state-event table 1 – events .58
Table 40 – M2 master state-event table 2 – receipt of FSPM service primitives .59
Table 41 – M2 master state-event table 3 – receipt of DMPM service primitives.59
Table 42 – S1 connect monitoring time .61
Table 43 – S2 connect monitoring time .61
Table 44 – Slave state-event table 1 – events.62
Table 45 – Slave state-event table 2 – receipt of FSPM service primitives .62
Table 46 – Slave state-event table 3 – receipt of DMPM service primitives .62
Table 47 – ARPM to DL mapping .63
Table 48 – DL to ARPM mapping .63

61158-6-18 © IEC:2007(E) – 5 –

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
INDUSTRIAL COMMUNICATION NETWORKS –

FIELDBUS SPECIFICATIONS –
Part 6-18: Application layer service definition – Type 18 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
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
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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
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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.
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.
IEC draws attention to the fact that it is claimed that compliance with this standard may involve the use of patents
as follows, where the [xx] notation indicates the holder of the patent right:
Type 18:
3343036/Japan [MEC] “Network System for a Programmable Controller”
5896509/USA [MEC] “Network System for a Programmable Controller”
246906/Korea [MEC] “Network System for a Programmable Controller”
Pending/Germany [MEC] “Network System for a Programmable Controller”

IEC takes no position concerning the evidence, validity and scope of these patent rights.
The holders of these patent rights have assured IEC that they are willing to negotiate licences under reasonable
and non-discriminatory terms and conditions with applicants throughout the world. In this respect, the statement of
the holders of these patent rights are registered with IEC. Information may be obtained from:
[MEC] Mitsubishi Electric Corporation
Corporate Licensing Deivsion
7-3, Marunouchi 2-chome, Chiyoda-ku,
Tokyo 100-8310, Japan
– 6 – 61158-6-18 © IEC:2007(E)

Attention is drawn to the possibility that some of the elements of this standard may be the subject of patent rights

other than those identified above. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 61158-6-18 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 a technical addition.

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;
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.

61158-6-18 © IEC:2007(E) – 7 –

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.

– 8 – 61158-6-18 © IEC:2007(E)

INDUSTRIAL COMMUNICATION NETWORKS –

FIELDBUS SPECIFICATIONS –
Part 6-18: Application layer protocol specification – Type 18 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 18 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 specifies interactions between remote applications and defines the externally
visible behavior provided by the Type 18 fieldbus application layer in terms of
a) the formal abstract syntax defining the application layer protocol data units conveyed
between communicating application entities;
b) the transfer syntax defining encoding rules that are applied to the application layer
protocol data units;
c) the application context state machine defining the application service behavior visible
between communicating application entities;
d) the application relationship state machines defining the communication behavior visible
between communicating application entities.
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- 5-18, and
2) define the externally visible behavior associated with their transfer.
This standard specifies the protocol of the Type 18 fieldbus application layer, in conformance

with the OSI Basic Reference Model (ISO/IEC 7498) and the OSI application layer structure
(ISO/IEC 9545).
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 61158-5-18.
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 the IEC 61158-6 series.
1.3 Conformance
This standard does not specify individual implementations or products, nor do they constrain
the implementations of application layer entities within industrial automation systems.

61158-6-18 © IEC:2007(E) – 9 –

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 61158-5-18, Industrial communication networks – Fieldbus specifications – Part 5-18:

Application layer service definition – Type 18 elements

ISO/IEC 10731, Information technology – Open Systems Interconnection – Basic Reference
Model – Conventions for the definition of OSI services
ISO/IEC 7498-1, Information technology – Open Systems Interconnection – Basic Reference
Model – Part 1: The Basic Model
ISO/IEC 8822, Information technology – Open Systems Interconnection – Presentation
service definition
ISO/IEC 8824, Information technology – Open Systems Interconnection – Specification of
Abstract Syntax Notation One (ASN.1)
ISO/IEC 9545, Information technology – Open Systems Interconnection – Application Layer
structure
3 Terms and definitions
3.1 Terms and definitions from other ISO/IEC standards
3.1.1 ISO/IEC 7498-1 terms
For the purposes of this document, the following terms as defined in ISO/IEC 7498-1 apply:
a) application entity
b) application process
c) application protocol data unit
d) application service element
e) application entity invocation

f) application process invocation
g) application transaction
h) real open system
i) transfer syntax
3.1.2 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
3.1.3 ISO/IEC 9545 terms
For the purposes of this document, the following terms as defined in ISO/IEC 9545 apply:

– 10 – 61158-6-18 © IEC:2007(E)

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
3.1.4 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
3.2 Other terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.2.1
active connection control object
instance of a certain FAL class that abstracts the interconnection facility (as Consumer and
Provider) of an automation device
3.2.2
alarm
activation of an event that shows a critical state
3.2.3
alarm ack
acknowledgment of an event that shows a critical state
3.2.4
alarm data object
object(s) which represent critical states referenced by device/slot/subslot/alarm type
3.2.5
allocate
take a resource from a common area and assign that resource for the exclusive use of a
specific entity
3.2.6
application
function or data structure for which data is consumed or produced
3.2.7
application layer interoperability
capability of application entities to perform coordinated and cooperative operations using the
services of the FAL
3.2.8
application objects
multiple object classes that manage and provide a run time exchange of PDUs across the
network and within the network device

61158-6-18 © IEC:2007(E) – 11 –

3.2.9
application process
part of a distributed application on a network, which is located on one device and

unambiguously addressed
3.2.10
application process identifier

distinguishes multiple application processes used in a device

NOTE  Application process identifier is assigned by PROFIBUS International (PI).

3.2.11
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.
3.2.12
application process object class
a class of application process objects defined in terms of the set of their network-accessible
attributes and services
3.2.13
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
3.2.14
application relationship application service element
application-service-element that provides the exclusive means for establishing and
terminating all application relationships
3.2.15
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.
3.2.16
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 behavior of an object.
Attributes are divided into class attributes and instance attributes.
3.2.17
backup
status of the IO AR, which indicates that it, is in the standby state
3.2.18
behavior
indication of how an object responds to particular events

– 12 – 61158-6-18 © IEC:2007(E)

3.2.19
channel
representation of a single physical or logical link of an input or output application object of a

server to the process in order to support addressing of diagnosis information

NOTE  The channel typically represents a single connector or clamp as a real interface of a module or sub-module.
This reference is used to identify points of failure within diagnosis PDUs.

3.2.20
channel related diagnosis
information concerning a specific element of an input or output application object, provided for

maintenance purposes
EXAMPLE  open loop.
3.2.21
class
a set of objects, all of which represent the same kind of system component
NOTE  A class is a generalization of an object; a template for defining variables and methods. All objects in a
class are identical in form and behavior, but usually contain different data in their attributes.
3.2.22
class attributes
attribute that is shared by all objects within the same class
3.2.23
class code
unique identifier assigned to each object class
3.2.24
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.
3.2.25
clear
status of the IO controller, which indicates that the control algorithm is currently not running
3.2.26
client
a) object which uses the services of another (server) object to perform a task
b) initiator of a PDU to which a server reacts
3.2.27
common profile
a collection of device independent information and functionality providing consistency
between all devices
3.2.28
communication data object
object(s) which are parameter of communication relationships and referenced by device/slot/
subslot/ index
61158-6-18 © IEC:2007(E) – 13 –

3.2.29
configuration check
comparison of the expected IO-Data object structuring of the client with the real IO-Data

object structuring to the server in the start-up phase

3.2.30
configuration data base
interconnection information maintained by the ACCO ASE

3.2.31
configuration fault
an unacceptable difference between the expected IO-Data object structuring and the real IO-
Data object structuring, as detected by the server
3.2.32
configuration identifier
representation of a portion of IO Data of a single input- and/or output-module of a server
3.2.33
connection
the logical link between sink and source of attributes and services at different custom
interfaces of Custom RT-Auto objects
3.2.34
connection channel
description of a connection between a sink and a source of data items
3.2.35
consume
act of receiving data from a provider
3.2.36
consumer
node or sink that is receiving data from a producer
3.2.37
consumerID
unambiguous identifier within the scope of the ACCO assigned by the consumer to recognize
the internal data of a configured interconnection sink.
3.2.38
context management
network-accessible information (communication objects) that supports managing the operation
of the fieldbus system, including the application layer
NOTE  Managing includes functions such as controlling, monitoring, and diagnosing.
3.2.39
conveyance path
unidirectional flow of APDUs across an application relationship
3.2.40
cyclic
repetitive in a regular manner

– 14 – 61158-6-18 © IEC:2007(E)

3.2.41
data consistency
means for coherent transmission and access of the input- or output-data object between and

within client and server
3.2.42
data marshaling
the encoding of parameters of the FAL service primitives with respect to their interface

definition
NOTE  This is part of the abstract ORPC model.

3.2.43
device
physical hardware connected to the link
NOTE  A device may contain more than one node.
3.2.44
device ID
a vendor assigned device type identification
3.2.45
device profile
a collection of device dependent information and functionality providing consistency between
similar devices of the same device type
3.2.46
diagnosis data object
object(s) which contains diagnosis information referenced by device/slot/subslot/index
3.2.47
diagnosis information
all data available at the server for maintenance purposes
3.2.48
dynamic reconfiguration
change of IO data objects without interruption of an established application relationship and
continuous updating of non-changed IO data objects
3.2.49
endpoint
one of the communicating entities involved in a connection
3.2.50
engineering
abstract term that characterizes the client application or device responsible for configuring an
automation system via interconnecting data items
3.2.51
error
discrepancy between a computed, observed or measured value or condition and the specified
or theoretically correct value or condition
3.2.52
error class
general grouping for related error definitions and corresponding error codes

61158-6-18 © IEC:2007(E) – 15 –

3.2.53
error code
identification of a specific type of error within an error class

3.2.54
event
an instance of a change of conditions

3.2.55
extended channel related diagnosis

information concerning a specific element of a specific application object, provided for

maintenance purposes
EXAMPLE  Link Fail.
3.2.56
frame
denigrated term for DLPDU, unit of data transfer on a link
3.2.57
identification data object
object(s) that contain information about device, module and sub-module manufacturer and
type referenced by device/slot/subslot/index
3.2.58
implicit AR endpoint
AR endpoint that is defined locally within a device without use of the create service
3.2.59
index
address of a record data object within an application process
3.2.60
instance
the actual physical occurrence of an object within a class that identifies one of many objects
within the same object class
3.2.61
instance attributes
attribute that is unique to an object instance and not shared by the object class
3.2.62
instantiated
object that has been created in a device
3.2.63
interface
collection of FAL class attributes and services that represents a specific view on the FAL
class
3.2.64
interface definition language
syntax and semantic of describing service parameters in a formal way
NOTE  This description is the input for the ORPC model, especially for the ORPC wire protocol.
3.2.65
interface pointer
key attribute that unambiguously addresses an object interface instance

– 16 – 61158-6-18 © IEC:2007(E)

3.2.66
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. Also for

service invocations, an Invoke ID may be used to unambiguously identify the service invocation and differentiate it

from other outstanding service invocations.

3.2.67
IO controller
controlling device, which acts as client for several IO devices (field devices)

NOTE  This is usually a programmable controller or a distributed control system.
3.2.68
IO data object
object designated to be transferred cyclically for the purpose of processing and referenced by
device/slot/subslot
3.2.69
IO device
field device which acts as server for IO operation
3.2.70
IO parameter server
server for application parameter of IO devices (client)
NOTE  This is usually a device to backup parameter data and to log online changes of device parameter.
3.2.71
IO subsystem
subsystem composed of one IO controller and all its associated IO devices
3.2.72
IO supervisor
engineering device which manages commissioning and diagnosis of an IO system
3.2.73
IO system
system composed of all its IO subsystems
NOTE  As an example a PLC with more than one IO controller (network interface) controls one IO system

composed of an IO subsystems for each IO controller.
3.2.74
Isochronous mode
IO system operating tightly synchronized with a jitter of less than 1 µs
3.2.75
logical device
a certain FAL class that abstracts a software component or a firmware component as an
autonomous self-contained facility of an automation device
3.2.76
member
piece of an attribute that is structured as an element of an array

61158-6-18 © IEC:2007(E) – 17 –

3.2.77
method
a synonym for an operational service which is provided by the server ASE and

invoked by a client
3.2.78
module
hardware or logical component of a physical device

3.2.79
network
a set of nodes connected by some type of communication medium, including any intervening
repeaters, bridges, routers and lower-layer gateways
3.2.80
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 behavior
3.2.81
object remote procedure call
model for object oriented or component based remote method invocation
3.2.82
object specific service
service unique to the object class which defines it
3.2.83
operate
status of the IO controller that indicates that the control algorithm is currently running
3.2.84
peer
role of an AR endpoint in which it is capable of acting as both client and server
3.2.85
physical device
a certain FAL class that abstracts the hardware facilities of an automation device
3.2.86
point-to-point connection
connection that exists between exactly two application objects
3.2.87
primary
status of the IO AR that indicates that it is in the operating state
NOTE  Besides a primary IO AR a backup IO AR may exist. In example used for redundancy and dynamic
reconfiguration of IO data.
3.2.88
property
a synonym for ASE attributes which are readable or writeable via operational ASE services
NOTE  These services are generally named “get_” or “set_” and correspond
with the IDL keywords “propget” and “propput”.

– 18 – 61158-6-18 © IEC:2007(E)

3.2.89
provider
a) source of a data connection

b) node or source sending data to one or many consumer

3.2.90
providerID
an unambiguous identifier within the scope of the ACCO assigned by the provider to

recognize the internal data of a configured connection source

3.2.91
PTCP domain
a certain number of PTCP subdomains in one IP subnet
3.2.92
PTCP subdomain
a certain amount of DTEs with synchronized clocks
3.2.93
quality code
additional status information of a data item
3.2.94
quality code aware
attribute of the RT-Auto class that indicates that an RT-Auto object uses a status code for its
data items
3.2.95
quality code unaware
opposite of quality code aware
3.2.96
record data object
object(s) which are already pre-processed and transferred acyclically for the purpose of
informa
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