IEC 61158-5-15:2007

IEC 61158-5-15
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 5-15: Application layer service definition – Type 15 elements

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IEC 61158-5-15
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 5-15: Application layer service definition – Type 15 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XF
ICS 35.100.70; 25.040.40 ISBN 2-8318-9466-2

– 2 – 61158-5-15 © IEC:2007(E)

CONTENTS
FOREWORD.5

INTRODUCTION.7

1 Scope.8

1.1 Overview .8

1.2 Specifications.9

1.3 Conformance.9

1.4 Type overview .9

2 Normative references .10
3 Terms and definitions, abbreviations, symbols and conventions .10
3.1 Terms and definitions .10
3.2 Abbreviations and symbols.18
3.3 Conventions .19
4 Concepts .23
4.1 Common concepts.23
4.2 Client/server specific concepts .23
4.3 Publish/subscribe specific concepts .31
5 Data type ASE.40
5.1 General .40
5.2 Formal definition of data type objects .40
5.3 FAL defined data types.40
5.4 Data type ASE service specification .53
6 Client/server communication model specification.54
6.1 ASEs.54
6.2 ARs .113
6.3 Summary of FAL classes .115
6.4 Permitted FAL services by AREP role. 116
7 Publish/subscribe communication model specification . 117
7.1 ASEs.117
7.2 ARs .136
7.3 Summary of FAL classes .138
7.4 Permitted FAL services by AREP role and sub-role . 138

Bibliography.139

Figure 1 – Client/server stacks.23
Figure 2 – Client/server communication on different buses or networks .23
Figure 3 – Client/server APOs services conveyed by the FAL .24
Figure 4 – [INFORMATIVE] Interpretation as distinct tables .25
Figure 5 – [INFORMATIVE] Interpretation as overlapping tables .26
Figure 6 – [INFORMATIVE] APO and real objects, non obvious possible interpretation .26
Figure 7 – ASE service conveyance.28
Figure 8 – Client/server confirmed interaction .29
Figure 9 – Client/server AR confirmed service primitives (positive case) .30
Figure 10 – Client/server AR confirmed service primitives (negative case).30
Figure 11 – Client/server unconfirmed interaction .31

61158-5-15 © IEC:2007(E) – 3 –

Figure 12 – Client/server AR unconfirmed service primitives.31

Figure 13 – Publish/subscribe communications stacks .32

Figure 14 – Publish/subscribe data-centric exchanges between decoupled network

objects.33

Figure 15 – Publish/subscribe APOs services conveyed by the FAL.34

Figure 16 – [INFORMATIVE] Examples of publish/subscribe configurable behaviors via

QoS.35

Figure 17 – Pull model interactions .37

Figure 18 – Push model interactions .38

Figure 19 – Publish/subscribe model interactions.39
Figure 20 – FAL ASEs .55
Figure 21 – Client/server encapsulated interface mechanism .102
Figure 22 – Publish/subscribe class derivations and relationships. 117
Figure 23 – FAL ASEs and classes .118
Figure 24 – Publish/subscribe service request composition. 128

Table 1 – Common client/server APOs.25
Table 2 – Class identification .48
Table 3 – Assigned vendor IDs .49
Table 4 – Filter service parameters.57
Table 5 – Read discretes service parameters.59
Table 6 – Read coils service parameters .63
Table 7 – Write single coil service parameters .64
Table 8 – Write multiple coils service parameters .66
Table 9 – Broadcast write single coil service parameters .67
Table 10 – Broadcast write multiple coils service parameters.68
Table 11 – Read input registers service parameters.71
Table 12 – Read holding registers service parameters .76
Table 13 – Write single holding register service parameters.78
Table 14 – Write multiple holding registers service parameters .79
Table 15 – Mask write holding register service parameters .81
Table 16 – Read/write holding registers service parameters .83

Table 17 – Read FIFO service parameters.85
Table 18 – Broadcast write single holding register service parameters.86
Table 19 – Broadcast write multiple holding registers service parameters .87
Table 20 – Read file service parameters .94
Table 21 – Write file service parameters .98
Table 22 – Device identification categories .104
Table 23 – Read device ID code .105
Table 24 – Conformity level .106
Table 25 – Requested vs. returned known objects .107
Table 26 – Read device identification service parameters.109
Table 27 – FAL class summary .115
Table 28 – Services by AREP role .116

– 4 – 61158-5-15 © IEC:2007(E)

Table 29 – Issue service parameters .120

Table 30 – Heartbeat service parameters.121

Table 31 – VAR service parameters.123

Table 32 – VAR service parameters.125

Table 33 – ACK service parameters.127

Table 34 – Header service parameters .130

Table 35 – INFO_DST service parameters .131

Table 36 – INFO_REPLY service parameters.132

Table 37 – INFO_SRC service parameters.134
Table 38 – INFO_TS service parameters .135
Table 39 – PAD service parameters.136
Table 40 – FAL class summary .138
Table 41 – Services by AREP role and sub-role. 138

61158-5-15 © IEC:2007(E) – 5 –

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
INDUSTRIAL COMMUNICATION NETWORKS –

FIELDBUS SPECIFICATIONS –
Part 5-15: Application layer service definition – Type 15 elements

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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6) All users should ensure that they have the latest edition of this publication.
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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 of their respective intellectual-property-right holders.
International Standard IEC 61158-5-15 has been prepared by subcommittee 65C: Industrial
technical committee 65: Industrial-process measurement, control and
networks, of IEC
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 part and its
Type 15 companion parts also cancel and replace IEC/PAS 62030, published in 2004.
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;

– 6 – 61158-5-15 © IEC:2007(E)

c) partition of part 5 of the third edition into multiple parts numbered -5-2, -5-3, …

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.

61158-5-15 © 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 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.

– 8 – 61158-5-15 © IEC:2007(E)

INDUSTRIAL COMMUNICATION NETWORKS –

FIELDBUS SPECIFICATIONS –
Part 5-15: Application layer service definition – Type 15 elements

1 Scope
1.1 Overview
In network communications, as in many fields of engineering, it is a fact that “one size does

not fit all.” Engineering design is about making the right set of trade-offs, and these trade-offs
must balance conflicting requirements such as simplicity, generality, ease of use, richness of
features, performance, memory size and usage, scalability, determinism, and robustness.
These trade-offs must be made in light of the types of information flow (e.g. periodic, one-to-
many, request-reply, events), and the constraints imposed by the application and execution
platforms.
The Type 15 fieldbus provides two major communication mechanisms that complement each
others to satisfy communication requirements in the field of automation: the Client/Server and
the Publish/Subscribe paradigms. They can be used concurrently on the same device.
Type 15 Client/Server operates in a Client/Server relationship. Its application layer service
definitions and protocol specifications are independent of the underlying layers, and have
been implemented on a variety of stacks and communication media, including EIA/TIA-232,
EIA/TIA-422, EIA/TIA-425, HDLC (ISO 13239), fiber, TCP/IP, Wireless LANs and Radios.
Type 15 Publish/Subscribe operates in a Publish/Subscribe relationship. Its application layer
service definitions and protocol specifications are independent of the underlying layers and
can be configured to provide reliable behaviour and support determinism. The most common
stack is UDP/IP.
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 part of IEC 61158 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 15 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 part of IEC 61158 define in an abstract way the externally visible service provided by the
Type 15 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 part of IEC 61158 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
61158-5-15 © IEC:2007(E) – 9 –

2) Systems Management at the boundary between the Application Layer and Systems

Management of the Fieldbus Reference Model.

This part of IEC 61158 specifies the structure and services of the Type 15 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.
1.2 Specifications
The principal objective of this part of IEC 61158 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 part of IEC 61158 does not specify individual implementations or products, nor do they
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 15 application layer services as defined in this part of
IEC 61158.
1.4 Type overview
In network communications, as in many fields of engineering, it is a fact that “one size does
not fit all.” Engineering design is about making the right set of trade-offs, and these trade-offs
must balance conflicting requirements such as simplicity, generality, ease of use, richness of
features, performance, memory size and usage, scalability, determinism, and robustness.
These trade-offs must be made in light of the types of information flow (e.g. periodic, one-to-

– 10 – 61158-5-15 © IEC:2007(E)

many, request-reply, events), and the constraints imposed by the application and execution

platforms.
The Type 15 fieldbus provides two major communication mechanisms that complement each

others to satisfy communication requirements in the field of automation: the Client/Server and

the Publish/Subscribe paradigms. They can be used concurrently on the same device.

Type 15 Client/Server operates in a Client/Server relationship. Its application layer service

definitions and protocol specifications are independent of the underlying layers, and have

been implemented on a variety of stacks and communication media, including EIA/TIA-232,

EIA/TIA-422, EIA/TIA-425, HDLC (ISO 13239), fiber, TCP/IP, Wireless LANs and Radios.

Type 15 Publish/Subscribe operates in a Publish/Subscribe relationship. Its application layer
service definitions and protocol specifications are independent of the underlying layers and
can be configured to provide reliable behavior and support determinism. The most common
stack is UDP/IP.
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/TR 61158-1 (Ed.2.0), Industrial communication networks – Fieldbus specifications – Part
1: Overview and guidance for the IEC 61158 and IEC 61784 series
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
ISO/IEC 10731, Information technology – Open Systems Interconnection – Basic Reference
Model – Conventions for the definition of OSI services

3 Terms and definitions, abbreviations, symbols and conventions
3.1 Terms and definitions
For the purposes of this document, the following terms as defined in these publications apply:
3.1.1 ISO/IEC 7498-1 terms
a) application entity
b) application process
c) application protocol data unit
d) application service element
e) application entity invocation
f) application process invocation

61158-5-15 © IEC:2007(E) – 11 –

g) application transaction
h) real open system
i) transfer syntax
3.1.2 ISO/IEC 8822 terms
a) abstract syntax
b) presentation context
3.1.3 ISO/IEC 9545 terms
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
a) object identifier
b) type
3.1.5 IEC/TR 61158-1 terms
The following IEC/TR 61158-1 terms apply.
3.1.5.1 application
function or data structure for which data is consumed or produced
3.1.5.2 application layer interoperability
capability of application entities to perform coordinated and cooperative operations using the
services of the FAL
3.1.5.3 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.
3.1.5.4 application process
part of a distributed application on a network, which is located on one device and
unambiguously addressed
3.1.5.5 application process identifier
distinguishes multiple application processes used in a device

– 12 – 61158-5-15 © IEC:2007(E)

3.1.5.6 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.

3.1.5.7 application process object class

class of application process objects defined in terms of the set of their network-accessible

attributes and services
3.1.5.8 application relationship
cooperative association between two or more application-entity-invocations for the purpose of
exchange of information and coordination of their joint operation
NOTE  This relationship is activated either by the exchange of application-protocol-data-units or as a result of
preconfiguration activities.
3.1.5.9 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.
3.1.5.10 application service element
application-service-element that provides the exclusive means for establishing and
terminating all application relationships
3.1.5.11 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.
3.1.5.12 behavior
indication of how the object responds to particular events
NOTE  Its description includes the relationship between attribute values and services.
3.1.5.13 class
set of objects, all of which represent the same kind of system component
NOTE  A class is a generalization of the 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.
3.1.5.14 class attributes
attribute that is shared by all objects within the same class
3.1.5.15 class code
unique identifier assigned to each object class
3.1.5.16 class specific service
service defined by a particular object class to perform a required function which is not
performed by a common service
61158-5-15 © IEC:2007(E) – 13 –

NOTE  A class specific object is unique to the object class which defines it.

3.1.5.17 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, 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

3.1.5.18 conveyance path
unidirectional flow of APDUs across an application relationship

3.1.5.19 cyclic
term used to describe events which repeat in a regular and repetitive manner
3.1.5.20 dedicated AR
AR used directly by the FAL user
NOTE  On Dedicated ARs, only the FAL Header and the user data are transferred.
3.1.5.21 device
physical hardware connection to the link
NOTE  A device may contain more than one node.
3.1.5.22 device profile
collection of device dependent information and functionality providing consistency between
similar devices of the same device type
3.1.5.23 dynamic AR
AR that requires the use of the AR establishment procedures to place it into an established
state
3.1.5.24 endpoint
one of the communicating entities involved in a connection
3.1.5.25 error
discrepancy between a computed, observed or measured value or condition and the specified
or theoretically correct value or condition
3.1.5.26 error class
general grouping for error definitions
NOTE  Error codes for specific errors are defined within an error class.
3.1.5.27 error code
identification of a specific type of error within an error class
3.1.5.28 FAL subnet
networks composed of one or more data link segments

– 14 – 61158-5-15 © IEC:2007(E)

NOTE  Subnets are permitted to contain bridges, but not routers. FAL subnets are identified by a subset of the

network address.
3.1.5.29 logical device
FAL class that abstracts a software component or a firmware component as an autonomous

self-contained facility of an automation device

3.1.5.30 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.
3.1.5.31 network
series of nodes connected by some type of communication medium
NOTE  The connection paths between any pair of nodes can include repeaters, routers and gateways.
3.1.5.32 peer
role of an AR endpoint in which it is capable of acting as both client and server
3.1.5.33 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.
3.1.5.34 pre-established AR endpoint
AR endpoint that is placed in an established state during configuration of the AEs that control
its endpoints
3.1.5.35 publisher
role of an AR endpoint in which it transmits APDUs onto the fieldbus for consumption by one
or more subscribers
NOTE  The publisher may not be aware of the identity or the number of subscribers and it may publish its APDUs
using a dedicated AR. Two types of publishers are defined by this standard, Pull Publishers and Push Publishers,
each of which is defined separately.
3.1.5.36 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
3.1.5.37 service
operation or function than an object and/or object class performs upon request from another
object and/or object class
NOTE  A set of common services is defined and provisions for the definition of object-specific services are
provided. Object-specific services are those which are defined by a particular object class to perform a required
function which is not performed by a common service.
3.1.5.38 subscriber
role of an AREP in which it receives APDUs produced by a publisher

61158-5-15 © IEC:2007(E) – 15 –

NOTER  Two types of subscribers are defined by this standard, pull subscribers and push subscribers, each of

which is defined separately.
3.1.6 Specific definitions for client/server

3.1.6.1
coils, discrete outputs
application process object, a set of coils, characterized by the address of a coil and a quantity

of coils, this set is also called discrete outputs when associated with field outputs

3.1.6.2
discrete, discrete input
application process object, addressed by an unsigned number and having a width of one bit,
representing a 1-bit encoded status value, read-only, with the value '1' encoding the status
ON and the value '0' encoding the status OFF, also called discrete input, especially when
associated with field outputs
3.1.6.3
discrete inputs, discretes
application process object, a set of discretes, characterized by the address of a discrete and
a quantity of discretes, this set is also called discrete inputs, especially when associated with
field inputs
3.1.6.4
coil, discrete output
application process object, addressed by an unsigned number and having a width of one bit,
representing a 1-bit encoded status value, read-write, with the value '1' encoding the status
ON and the value '0' encoding the status OFF, also called discrete output when associated
with field output
3.1.6.5
encapsulated interface
mechanism encapsulating a service for an interface, which is an application process object
characterized by an MEI type
3.1.6.6
exception
encoding used to signal a service request failure
3.1.6.7
exception code
encoding associated with an exception, detailing the reason of a service request failure

3.1.6.8
file
application process object, an organization of records, characterized by an unsigned number
3.1.6.9
function code
encoding of a service requested to a server
3.1.6.10
holding register,output register
application process object, addressed by an unsigned number and representing values with
16 bits, read-write
– 16 – 61158-5-15 © IEC:2007(E)

3.1.6.11
holding registers, output registers

application process object, a set of holding registers, characterized by the address of a

holding register and a quantity of holding registers

3.1.6.12
input register
application process object, addressed by an unsigned number and representing values with

16 bits, read-only
3.1.6.13
input registers
application process object, a set of input registers, characterized by the address of an input
register and a quantity of input registers
3.1.6.14
record
application process object, a set of contiguous registers of a specified type, characterized by
the address of the first register and by the quantity of registers; in the context of this
definition, the registers involved have also been called references
3.1.6.15
reference
denigrated term for register
3.1.6.16
reference type
denigrated term for register type
3.1.6.17
sub-code
specialization of a function code
3.1.6.18
unit ID
logical device identifier
3.1.6.19
MEI type
type specified as an octet value, used to dispatch a service to the appropriate interface in the
context of the encapsulated interface mechanism

3.1.7 Specific definitions for publish/subscribe
3.1.7.1
network object
publish/subscribe application, reader, or writer
3.1.7.2
GUID
globally unique network object identifier, used to uniquely reference an object within the
network
3.1.7.3
composite state
attributes of a set of network objects

61158-5-15 © IEC:2007(E) – 17 –

3.1.7.4
composite state transfer
Interactions between CSTWriters and interested CSTReaders with the goal to allow the

CSTReaders to reconstruct the composite state of the communicating CSTWriter, without

transferring the entire history that led to the current composite state of that CSTWriter.

3.1.7.5
reader
subscriber or a CSTReader
3.1.7.6
writer
publisher or a CSTWriter
3.1.7.7
CSTReader
meta-information-specialized subscriber
3.1.7.8
CSTWriter
meta-information-specialized publisher
3.1.7.9
communication actor
reader or writer
3.1.7.10
domain participant
application that uses publish/subscribe elements, also called publish/subscribe application
NOTE  This terminology is adopted to avoid the overuse of the term “application”. At the same time, the term
“domain” has a place within publish/subscribe. The Type extensibility allows for the concept of “domains”, or
independent communication planes, effectively permitting isolation of application exchanges within domains. While
OMG DDS as in “Data Distribution Service for Real-Time Systems Specification, Version 1.1, December 2005” uses
this extension, the feature will not be examined further in this specification, which will consider a single domain.
3.1.7.11
manager
specialized publish/subscribe application, containing specialized publishers and subscribers,
and involved in the described discovery and maintenance mechanism; not to be confused with
any publishing manager
3.1.7.12
managed participant
a publish/subscribe application; the qualifier refers to its role in relation to a manager when
in
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