SIST EN 61158-3-17:2008

Industrial communication networks - Fieldbus specifications - Part 3-17: Data-link layer service definition - Type 17 elements

It provides common elements for basic time-critical messaging communications between devices in an automation environment. 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. It includes the following significant changes with respect to the previous edition deletion of the former Type 6 fieldbus, and the placeholder for a Type 5 fieldbus data-link layer, for lack of market relevance; addition of new types of fieldbuses; division of this part into multiple parts numbered.

Industrielle Kommunikationsnetze - Feldbusse - Teil 3-17: Dienstfestlegungen des Data Link Layer (Sicherungsschicht) - Typ 17-Elemente

Réseaux de communication industriels - Spécifications des bus de terrain - Partie 3-17: Définition des services des couches de liaison de données - Eléments de type 17

La CEI 61158-3-17:2007 définit de manière abstraite les services visibles de l'extérieur fournis par la couche de liaison de données de bus de terrain Type 17 en termes:
- des actions et événements primitifs de service;
- des paramètres associés à chaque action primitive et événement primitif, et la forme qu'ils prennent;
- de l'interrelation entre ces actions et événements, et leurs séquences valides. Cette première édition et ses parties associées de la sous-série de la CEI 61158-3 annulent et remplacent la CEI 61158-3:2003. L'édition de cette partie constitue un ajout technique. La présente partie et ses parties associées Type 17 annulent et remplacent aussi la CEI/PAS 62405 publiée en 2005. Cette édition inclut les changements suivants:
- suppression du précédent bus de terrain de Type 6 et du réceptacle (placeholder) pour une couche de liaison de données de bus de terrain de Type 5 en raison d'un manque de pertinence commerciale;
- ajout de nouveaux types de bus de terrain;
- division de cette partie en plusieurs parties numérotées 3-1, 3-2, ...., 3-19. La présente version bilingue (2013-07) correspond à la version anglaise monolingue publiée en 2007-12.

Industrijska komunikacijska omrežja - Specifikacije za procesna vodila - 3-17. del: Definicija opravil na nivoju podatkovnih povezav - Elementi tipa 17 (IEC 61158-3-17:2007)

General Information

• Status: Published
• Publication Date: 14-Apr-2008
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.100.20 - Data link layer
• ICS: 35.110 - Networking
• Technical Committee: MOV - Measuring equipment for electromagnetic quantities
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 14-Mar-2008
• Due Date: 19-May-2008
• Completion Date: 15-Apr-2008
• Mandate: M/490 - Standardisation mandate to the European Standardisation Organisations (ESOs) to support European Smart Grid deployment
• Ref Project: EN 61158-3-17:2008 - Industrial communication networks - Fieldbus specifications - Part 3-17: Data-link layer service definition - Type 17 elements

Relations

• Replaces: SIST EN 61158-3:2004 - Digital data communication for measurement and control - Fieldbus for use in industrial control systems -- Part 3: Data link service definition
• Effective Date: 28-Jan-2023
• Revised: SIST EN 61158-3:2004 - Digital data communication for measurement and control - Fieldbus for use in industrial control systems -- Part 3: Data link service definition
• Effective Date: 07-Jun-2022

Overview

EN 61158-3-17:2008 is a CLC/CENELEC-adopted part of the IEC 61158 family that defines the data-link layer service for Type 17 fieldbus protocols used in industrial automation. The standard provides common elements for basic time‑critical messaging between devices, specifying service primitives, management facilities and quality-of-service considerations needed where actions must complete within a defined time‑window to avoid equipment, plant or human risk.

Key topics

• Scope and safety context: Focus on time‑critical communications - the concept of a time‑window within which actions must be completed with defined certainty.
• DLSAP management service: Definitions and primitives for creating, deleting, binding and unbinding Data Link Service Access Points (e.g., CREATE, DELETE, BIND, UNBIND).
• Connectionless‑mode data‑link service: Service model for connectionless transfers, including UNITDATA primitives and associated quality of service parameters.
• DL‑management (DLM) service: Management primitives and events for run‑time control and monitoring (e.g., SET, GET, ACTION, EVENT).
• Addressing and network structure: Overview of addressing and topology considerations at the data‑link layer.
• Primitives, parameters and state models: Time‑sequence diagrams, state transitions and parameter definitions are included to implement consistent behavior across devices.
• Standards integration and IPR notes: The standard notes that some protocol types are subject to intellectual‑property restrictions and that permitted type combinations are specified in the IEC/EN 61784 series.

Applications

EN 61158-3-17 is intended for implementers and users of fieldbus systems where deterministic, time‑constrained messaging is required. Typical applications include:

• PLCs, I/O modules and device firmware that implement the data‑link layer for Type 17 fieldbus protocols
• Control and safety systems in process and factory automation where missed deadlines create hazard or equipment damage risk
• System integrators and OEMs designing networked control architectures for motion control, interlocking, and real‑time monitoring
• Standards bodies and test houses validating conformance at the data‑link layer

Who should use this standard

• Control engineers and system architects
• Device manufacturers and firmware developers
• Safety engineers and validation teams
• Test labs and certification bodies

Related standards

• EN/IEC 61158 series (other Part 3‑xx data‑link layer definitions)
• EN/IEC 61158‑4‑17, ‑5‑17, ‑6‑17 (physical, application mapping, etc. for Type 17) - referenced in the document
• IEC/EN 61784 series (specifies permitted combinations and protocol profiles)
• ISO/IEC OSI references cited for service definitions

Keywords: EN 61158-3-17, fieldbus, data-link layer, industrial communication networks, time-critical messaging, DLSAP management, connectionless-mode service, DL-management, IEC 61158, industrial automation.

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-2008
1DGRPHãþD
SIST EN 61158-3:2004
Industrijska komunikacijska omrežja - Specifikacije za procesna vodila - 3-17. del:
Definicija opravil na nivoju podatkovnih povezav - Elementi tipa 17 (IEC 61158-3-
17:2007)
Industrial communication networks - Fieldbus specifications - Part 3-17: Data-link layer
service definition - Type 17 elements
Industrielle Kommunikationsnetze - Feldbusse - Teil 3-17: Dienstfestlegungen des Data
Link Layer (Sicherungsschicht) - Typ 17-Elemente
Réseaux de communication industriels - Spécifications des bus de terrain - Partie 3-17:
Définition des services des couches de liaison de données - Eléments de type 17
Ta slovenski standard je istoveten z: EN 61158-3-17:2008
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
35.100.20 Podatkovni povezovalni sloj Data link layer
35.110 Omreževanje Networking
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 61158-3-17
NORME EUROPÉENNE
February 2008
EUROPÄISCHE NORM
ICS 35.100.20; 25.040.40 Partially supersedes EN 61158-3:2004

English version
Industrial communication networks -
Fieldbus specifications -
Part 3-17: Data-link layer service definition -
Type 17 elements
(IEC 61158-3-17:2007)
Réseaux de communication industriels -  Industrielle Kommunikationsnetze -
Spécifications des bus de terrain - Feldbusse -
Partie 3-17: Définition des services Teil 3-17: Dienstfestlegungen
des couches de liaison de données - des Data Link Layer (Sicherungsschicht) -
Eléments de type 17 Typ 17-Elemente
(CEI 61158-3-17:2007) (IEC 61158-3-17:2007)

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 61158-3-17:2008 E
Foreword
The text of document 65C/473/FDIS, future edition 1 of IEC 61158-3-17, 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 61158-3-17 on 2008-02-01.
This and the other parts of the EN 61158-3 series supersede EN 61158-3:2004.
With respect to EN 61158-3:2004 the following changes were made:
– deletion of Type 6 fieldbus, and the placeholder for a Type 5 fieldbus data-link layer, for lack of market
relevance;
– addition of new fieldbus types;
– partition into multiple parts numbered 3-1, 3-2, …, 3-19.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2008-11-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2011-02-01
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 61158-3-17:2007 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 61158-4-17 NOTE  Harmonized as EN 61158-4-17:2008 (not modified).
IEC 61158-5-17 NOTE  Harmonized as EN 61158-5-17:2008 (not modified).
IEC 61158-6-17 NOTE  Harmonized as EN 61158-6-17:2008 (not modified).
IEC 61784-2 NOTE  Harmonized as EN 61784-2:2008 (not modified).
__________
- 3 - EN 61158-3-17:2008
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)
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
ISO/IEC 10731 1994 Information technology - Open Systems - -
Interconnection - Basic Reference Model -
Conventions for the definition of OSI services

1)
ISO/IEC 8802-3 - Information technology - Telecommunications - -
and information exchange between systems -
Local and metropolitan area networks -
Specific requirements -
Part 3: Carrier sense multiple access with
collision detection (CSMA/CD) access method
and physical layer specifications

1)
IETF RFC 826 - Ethernet Address Resolution Protocol - -

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

IEC 61158-3-17
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 3-17: Data-link layer service definition – Type 17 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
U
ICS 35.100.20; 25.040.40 ISBN 2-8318-9421-2

– 2 – 61158-3-17 © IEC:2007(E)
CONTENTS
0HFOREWORD.58H4
1HINTRODUCTION.59H6
2H1 Scope.60H7
3H2 Normative reference .61H8
4H3 Definitions .62H8
5H3.1 Terms and definitions .63H8
6H3.2 Abbreviations and symbols.64H10
7H3.3 Conventions .65H11
8H4 Overview of the data-link layer service .66H11
9H4.1 General .67H12
10H4.2 Overview of network structure .68H13
11H4.3 Overview of addressing .69H13
12H4.4 Types of data-link service.70H13
13H5 DLSAP management service .71H14
14H5.1 Overview .72H14
15H5.2 Facilities of the DLSAP management service.73H14
16H5.3 Model of the DLSAP management service .74H14
17H5.4 Sequence of primitives at one DLSAP .75H14
18H5.5 Create .76H15
19H5.6 Delete .77H16
20H5.7 Bind .78H17
21H5.8 Unbind .79H19
22H6 Connectionless-mode data-link service.80H19
23H6.1 Overview .81H19
24H6.2 Facilities of the connectionless-mode data-link service.82H20
25H6.3 Model of the data-link service.83H20
26H6.4 Quality of service .84H21
27H6.5 Sequence of primitives .85H23
28H6.6 Connectionless-mode function.86H24
29H6.7 Types of primitives and parameters .87H24
30H7 DL-management Service .88H25
31H7.1 Scope and inheritance.89H25
32H7.2 Facilities of the DL-management service .90H26
33H7.3 Model of the DL-management service.91H26
34H7.4 Constraints on sequence of primitives .92H26
35H7.5 Set .93H26
36H7.6 Get.94H27
37H7.7 Action.95H28
38H7.8 Event .96H29
39HBibliography.97H30

40HFigure 1 – Sequence of primitives for the DLSAP management DLS .98H15
41HFigure 2 – Summary of DL-connectionless-mode service primitive time-sequence
diagrams .99H23
42HFigure 3 – State transition diagram for sequences of connectionless-mode primitives
at one DLSAP .100H24

61158-3-17 © IEC:2007(E) – 3 –
43HFigure 4 – Sequence of primitives for the DLM action service .101H26

44HTable 1 – Summary of DLSAP management primitives and parameters .102H14
45HTable 2 – DLSAP-management CREATE primitive and parameters.103H15
46HTable 3 – DLSAP-management DELETE primitive and parameters .104H16
47HTable 4 – DLSAP management BIND primitive and parameters.105H17
48HTable 5 – DLSAP management UNBIND primitive and parameter .106H19
49HTable 6 – Data delivery features of each type of service .107H21
50HTable 7 – Summary of DL-connectionless-mode primitives and parameters .108H23
51HTable 8 – DL-connectionless-mode UNITDATA transfer primitives and parameters .109H24
52HTable 9 – Summary of DL-management primitives and parameters .110H26
53HTable 10 – DLM-SET primitive and parameters .111H27
54HTable 11 – DLM-GET primitive and parameters.112H27
55HTable 12 – DLM-ACTION primitive and parameters.113H28
56HTable 13 – DLM-EVENT primitive and parameters .114H29

– 4 – 61158-3-17 © IEC:2007(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 3-17: Data-link layer service definition – Type 17 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.
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 61158-3-17 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 61158-3 subseries cancel and replace
IEC 61158-3:2003. This edition of this part constitutes a technical addition. This part and its
Type 17 companion parts also replace IEC/PAS 62405, published in 2005.
This edition includes the following significant changes with respect to the previous edition:
a) deletion of the former Type 6 fieldbus, and the placeholder for a Type 5 fieldbus data-link
layer, for lack of market relevance;
b) addition of new types of fieldbuses;
c) division of this part into multiple parts numbered 3-1, 3-2, …, 3-19.
This edition of this part constitutes an editorial revision.

61158-3-17 © IEC:2007(E) – 5 –
The text of this standard is based on the following documents:
FDIS Report on voting
65C/473/FDIS 65C/484/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 57Hhttp://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 – 61158-3-17 © 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.
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 data-link layer service defined in this standard is a conceptual architectural service,
independent of administrative and implementation divisions.

61158-3-17 © IEC:2007(E) – 7 –
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 3-17: Data-link layer service definition – Type 17 elements

1 Scope
This part of IEC 61158 provides common elements for basic time-critical messaging
communications between devices in an automation environment. 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
17 fieldbus data-link Layer in terms of
a) the primitive actions and events of the service;
b) the parameters associated with each primitive action and event, and the form which they
take; and
c) the interrelationship between these actions and events, and their valid sequences.
The purpose of this standard is to define the services provided to
• the Type 17 fieldbus application layer at the boundary between the application and data-
link layers of the fieldbus reference model, and
• systems management at the boundary between the data-link layer and systems
management of the fieldbus reference model;
• specifications
The principal objective of this standard is to specify the characteristics of conceptual data-link
layer services suitable for time-critical communications, and thus supplement the OSI Basic
Reference Model in guiding the development of data-link protocols for time-critical
communications. A secondary objective is to provide migration paths from previously-existing
industrial communications protocols.
This specification may be used as the basis for formal DL-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.
• Conformance
This standard does not specify individual implementations or products, nor does it constrain
the implementations of data-link entities within industrial automation systems.
There is no conformance of equipment to this data-link layer service definition standard.
Instead, conformance is achieved through implementation of the corresponding data-link
protocol that fulfills the Type 17 data-link layer services defined in this standard.

– 8 – 61158-3-17 © IEC:2007(E)
2 Normative reference
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For all other undated references, the
latest edition of the referenced document (including any amendments) applies.
ISO/IEC 7498-1, Information technology – Open Systems Interconnection — Basic Reference
Model: The Basic Model
ISO/IEC 7498-3, Information technology – Open Systems Interconnection — Basic Reference
Model: Naming and addressing
ISO/IEC 10731:1994, Information technology – Open Systems Interconnection – Basic
Reference Model – Conventions for the definition of OSI services
ISO/IEC 8802-3, Information technology – Telecommunications and information exchange
between systems – Local and metropolitan area networks – Specific requirements – Part 3:
Carrier sense multiple access with collision detection (CSMA/CD) access method and
physical layer specifications
Internet Engineering Task Force (IETF), Request for Comments (RFC):
RFC 826 Ethernet Address Resolution Protocol
(available at )
3 Definitions
For the purposes of this document, the following terms and definitions apply.
3.1 Terms and definitions
3.1.1 ISO/IEC 10731 terms
a) (N)-connection
b) (N)-entity
c) (N)-layer
d) (N)-service
e) (N)-service-access-point
f) confirm (primitive)
g) deliver (primitive)
h) indication (primitive)
i) request (primitive)
j) response (primitive)
3.1.2 Other terms and definitions
3.1.2.1
bridge
intermediate equipment that connects two or more segments using a data-link layer relay
function
3.1.2.2
domain
part of the RTE network consisting of one or two subnetwork(s)
NOTE Two subnetworks are required to compose a dual-redundant RTE network, and each end node in the
domain is connected to both of the subnetworks.

61158-3-17 © IEC:2007(E) – 9 –
3.1.2.3
domain master
station which performs diagnosis of routes to all other domains, distribution of network time to
nodes inside the domain, acquisition of absolute time from the network time master and
notification of status of the domain
3.1.2.4
domain number
numeric identifier which indicates a domain
3.1.2.5
external bridge
bridge to which neither internal bridges nor RTE stations are connected directly
3.1.2.6
interface port
physical connection point of an end node, which has an independent DL-address
3.1.2.7
internal bridge
bridge to which no routers, external bridges or nodes non-compliant with this specification are
connected directly
3.1.2.8
junction bridge
bridge to which at least one router, external bridge or node non-compliant with this
specification, and to which at least one internal bridge or RTE station is connected
3.1.2.9
link
physical communication channel between two nodes
3.1.2.10
network time master
station which distributes network time to domain masters
3.1.2.11
non-redundant interface node
node which has a single interface port
3.1.2.12
non-redundant station
station that consists of a single end node
NOTE “non-redundant station” is synonymous with “end node”.
3.1.2.13
path
logical communication channel between two nodes, which consists of one or two link(s)
3.1.2.14
redundant interface node
node with two interface ports one of which is connected to a primary network, while the other
is connected to a secondary network
3.1.2.15
redundant station
station that consists of a pair of end nodes

– 10 – 61158-3-17 © IEC:2007(E)
NOTE Each end node of a redundant station has the same station number, but has a different DL-address.
3.1.2.16
route
logical communication channel between two communication end nodes
3.1.2.17
router
intermediate equipment that connects two or more subnetworks using a network layer relay
function
3.1.2.18
RTE station
station with real-time capability
3.1.2.19
segment
communication channel that connects two nodes directly without intervening bridges
3.1.2.20
station
end node or a pair of end nodes that perform a specific application function
3.1.2.21
station number
numeric identifier which indicates a RTE station
3.1.2.22
subnetwork
part of a network that does not contain any routers. A subnetwork consists of end nodes,
bridges and segments
NOTE Every end node included in a subnetwork has the same IP network address.
3.2 Abbreviations and symbols
3.2.1 ISO/IEC 10731 abbreviations
OSI  Open Systems Interconnection
3.2.2 Other abbreviations and symbols
ASS Acknowledged sequence of unitdata transfer service
AUS Acknowledged unitdata transfer service
cnf Confirmation primitive
DL- Data-link layer (as a prefix)
DLE DL-entity (the local active instance of the data-link layer)
DLL DL-layer
DLM DL-management
DLMS DL-management service
DLPDU DL-protocol-data-unit
DLS DL-service
DLSAP DL-service-access-point
DLSDU DL-service-data-unit
FIFO First-in first-out (queuing method)
ind Indication primitive
61158-3-17 © IEC:2007(E) – 11 –
IP Internet protocol
ISO International Organization for Standardization
PDU Protocol data unit
MSS Multipoint sequence of unitdata transfer service
MUS Multipoint unitdata transfer service
QoS Quality of service
req Request primitive
rsp Response primitive
SAP Service access point
SDU Service data unit
ToS Type of service
UUS Unacknowledged unitdata transfer service
3.3 Conventions
This standard uses the descriptive conventions given in ISO/IEC 10731.
The service model, service primitives, and time-sequence diagrams used are entirely abstract
descriptions; they do not represent a specification for implementation.
Service primitives, used to represent service user/service provider interactions (see
ISO/IEC 10731), convey parameters that indicate information available in the user/provider
interaction.
This standard uses a tabular format to describe the component parameters of the DLS
primitives. The parameters that apply to each group of DLS primitives are set out in tables
throughout the remainder of this standard. Each table consists of up to six columns,
containing the name of the service parameter, and a column each for those primitives and
parameter-transfer directions used by the DLS:
⎯ the request primitive’s input parameters;
⎯ the request primitive’s output parameters;
⎯ the indication primitive’s output parameters;
⎯ the response primitive’s input parameters; and
⎯ the confirm primitive’s output parameters.
NOTE  The request, indication, response and confirm primitives are also known as requestor.submit,
acceptor.deliver, acceptor.submit, and requestor.deliver primitives, respectively (see ISO/IEC 10731).
One parameter (or part of it) is listed in each row of each table. Under the appropriate service
primitive columns, a code is used to specify the type of usage of the parameter on the
primitive and parameter direction specified in the column:
M — parameter is mandatory for the primitive.
U — parameter is a User option, and may or may not be provided depending
on the dynamic usage of the DLS-user. When not provided, a default
value for the parameter is assumed.
C — parameter is conditional upon other parameters or upon the environment
of the DLS-user.
(blank) — parameter is never present.
Some entries are further qualified by items in brackets. These may be

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a) a parameter-specific constraint
(=) indicates that the parameter is semantically equivalent to the parameter in the
service primitive to its immediate left in the table;
b) an indication that some note applies to the entry
(n) indicates that the following note n contains additional information pertaining to the
parameter and its use.
In any particular interface, not all parameters need be explicitly stated. Some may be
implicitly associated with the DLSAP at which the primitive is issued.
In the diagrams which illustrate these interfaces, dashed lines indicate cause-and-effect or
time-sequence relationships, and wavy lines indicate that events are roughly
contemporaneous.
4 Overview of the data-link layer service
4.1 General
The data-link service (DLS) provides transparent and reliable data transfer between DLS-
users. It makes the way that supporting communication resources are utilized invisible to
DLS-users.
In particular, the DLS provides the following.
a) Independence from the underlying Physical Layer. The DLS relieves DLS-users from all
direct concerns regarding which configuration is available (for example, direct connection,
or indirect connection through one or more bridges) and which physical facilities are used
(for example, which of a set of diverse physical paths).
b) Transparency of transferred information. The DLS provides the transparent transfer of
DLS-user-data. It does not restrict the content, format or coding of the information, nor
does it ever need to interpret the structure or meaning of that information. It may, however,
restrict the amount of information that can be transferred as an indivisible unit.
c) Reliable data transfer. The DLS relieves the DLS-user from concerns regarding insertion
or corruption of data, or, if requested, loss, duplication or misordering of data, which can
occur. In some cases of unrecovered errors in the data-link layer, duplication or loss of
DLSDUs can occur. In cases where protection against misordering of data is not
employed, misordering can occur.
d) Quality of Service (QoS) selection. The DLS provides DLS-users with a means to request
and to agree upon a quality of service for the data transfer. QoS is specified by means of
QoS parameters representing aspects such as mode of operation, transit delay, accuracy,
reliability, security and functional safety.
e) Addressing. The DLS allows the DLS-user to identify itself and to specify the DLSAPs
to/from which data are to be transferred.
f) Scheduling. The DLS allows the set of DLS-users to provide some guidance on internal
scheduling of the distributed DLS-provider. This guidance supports the time-critical
aspects of the DLS, by permitting the DLS-user some degree of management over when
opportunities for communication will be granted to various DLEs for various DLSAP-
addresses.
g) Common time sense. The DLS can provide the DLS-user with a sense of time that is
common to all DLS-users on the network.
h) Queues. The DLS can provide the sending or receiving DLS-user with a FIFO queue,
where each queue item can hold a single DLSDU.

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4.2 Overview of network structure
Although the DLS conforms formally to the “three-layer” Fieldbus Reference Model, it actually
utilizes the transport layer service and the network layer service in addition to the data-link
layer service of the OSI Basic Reference Model. The DLS of this specification is actually a
transport layer service in terms of the OSI Basic Reference Model. Thus the network may
consist of one or more subnetworks interconnected to each other by the network layer relay
entities, known as routers.
A network may be a redundant structure. A redundant network consists of two independent
networks making dual-redundancy; they are referred to as the primary network and the
secondary network. Consequently, dual-redundant independent logical communication
channels between two communication end nodes can be implemented. This logical channel is
called a route.
A pair of subnetworks comprising a dual-redundant network is called a domain.
A subnetwork consists of one or more segments interconnected by DL-relay entities, known
as bridges. The topology of a subnetwork may be a tree, a ring or a mesh consisting of
segments interconnected by bridges.
A segment consists of one or more DLEs, all of which are connected directly (i.e., without
intervening DL-relay entities) to a single shared logical communication channel, which is
called a link.
A path (logical communication channel) consists of one or two physically independent and
logically parallel real communication channels, which are called links.
4.3 Overview of addressing
domain number
numeric identifier that indicates a domain. Two subnetworks comprising a dual-redundant
domain have an identical domain number.
station number
numeric identifier that indicates a RTE station. Two end nodes comprising a dual-redundant
station have an identical station number.
TSAP address
DL-entity actually provides transport layer services, so DLS is provided at TSAPs. TSAP is
identified by a set of TSAP-address (IP-address) and TSAP-identifier (UDP port number)
IP address
unique address for each end node. An IP address consists of a network address portion and a
host address portion. The network address is assigned according to the domain number, while
the host address is assigned based on the station number. Each end node of a dual-
redundant station has a different host address
MAC address
MAC address is a unique address for an end node defined in ISO/IEC 8802-3. The destination
MAC address is resolved by the mechanism defined in RFC 826 from the destination IP
address
4.4 Types of data-link service
There are three types of DLS as follows:
a) a DLSAP management service;
b) a connectionless-mode data transfer service;
c) a DL-management service.
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5 DLSAP management service
5.1 Overview
This clause provides a conceptual definition of the services provided by the DLS-provider to
the DLS-user(s). This clause does not constrain the actual implementations of the interactions
at the DLS-provider to the DLS-user interface.
5.2 Facilities of the DLSAP management service
The DLS provides the following facilities to the DLS-user:
a) a means for creating and deleting a FIFO queue of specified depth;
b) a means for assigning a DLSAP-address to the DLSAP;
c) a means for binding previously created FIFO queues to each potential direction of
connectionless data transfer at the specified DLSAP;
d) a means for specifying QoS parameters of the specified DLSAP;
e) a means for releasing resources used previously for the DLSAP.
5.3 Model of the DLSAP management service
This standard uses the abstract model for a layer service defined in ISO/IEC 10731, Clause 5.
The model defines interactions between the DLS-user and the DLS-provider that take place at
a DLSAP. Information is passed between the DLS-user and the DLS-provider by DLS
primitives that convey parameters.
The DLSAP management primitives are used to provide a local service between a DLS-user
and the local DLE. Remote DLEs and remote DLS-users are not involved direct, so there is no
need for the other primitives of ISO/IEC 10731. Therefore the DLSAP management services
are provided by request primitives with input and output parameters.
5.4 Sequence of primitives at one DLSAP
115HTable 1 is a summary of the DLSAP management primitives and parameters. The major
sequence of primitives at a single DLE is shown in 116HFigure 1.
Table 1 – Summary of DLSAP management primitives and parameters
Service Primitive Parameter
queue creation DL-CREATE request (in Queue DLS-user-identifier,
Maximum DLSDU size,
Maximum queue depth,
out Status,
Queue DL-identifier)
queue deletion DL-DELETE request (in Queue DL-identifier,
out Status)
DLSAP activation DL-BIND request (in DLSAP-address DLS-user-identifier,
Sending queue DL-identifier
Receiving queue DL-identifier,
QoS parameters,
out Status,
DLSAP-address DL-identifier)
DLSAP deactivation DL-UNBIND request (in DLSAP-address DL-identifier
out Status)
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DL-CREATE request
DL-BIND request
DL-UNITDATA request
or
DL-UNITDATA indication
DL-UNBIND request
DL-DELETE request
Figure 1 – Sequence of primitives for the DLSAP management DLS
5.5 Create
5.5.1 Function
The create queue DLS primitive may be used to create a limited-depth FIFO queue for later
constrained association with a DLSAP. The resulting FIFO queue initially will be empty.
5.5.2 Types of parameter
117HTable 2 lists the primitive and parameters of the create queue DLS.
Table 2 – DLSAP-management CREATE primitive and parameters
DL-CREATE Request
Parameter name input output
Queue DLS-user-identifier M
Maximum DLSDU size M
Maximum queue depth M
Status M
Queue DL-identifier C
5.5.2.1 Queue DLS-user-identifier
This parameter specifies a means of referring to the queue in output parameters of other local
DLS primitives that convey the name of the queue from the local DLE to the local DLS-user.
The naming-domain of the queue DLS-user-identifier is the DLS-user’s local-view.
5.5.2.2 Maximum DLSDU size
This parameter specifies an upper bound on the size (in octets) of DLSDUs that can be put
into the queue.
5.5.2.3 Maximum queue depth
This parameter specifies the maximum number of items in the associated queue.

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5.5.2.4 Status
This parameter allows the DLS-user to determine whether the requested DLS was provided
successfully, or failed for the reason specified. The possible value conveyed in this parameter
is as follows:
a) “success”;
b) “failure — insufficient resources”;
c) “failure — parameter violates management constraint”;
d) “failure — number of requests violates management constraint”; or
e) “failure — reason unspecified”.
NOTE  Addition to, or refinement of, this list of values to convey more specific diagnostic and management
information is permitted.
5.5.2.5 Queue DL-identifier
This parameter is present when the Status parameter indicates that the DL-CREATE request
primitive was successful. The queue DL-identifier parameter gives the local DLS-user a
means of referring to the queue in input parameters of other local DLS primitives that convey
the name of the queue from the local DLS-user to the local DLE.
5.6 Delete
5.6.1 Function
The delete queue DLS primitive may be used to delete a queue created by an earlier create
queue DLS primitive.
5.6.2 Types of parameter
118HTable 3 lists the primitive and parameters of the delete queue DLS.
Table 3 – DLSAP-management DELETE primitive and parameters
DL-DELETE Request
Parameter name input output
Queue DL-identifier M
Status M
5.6.2.1 Queue DL-identifier
This parameter specifies the local queue to be deleted. Its value is the queue DL-identifier
returned by a successful prior DL-CREATE request primitive. The DLS-provider will release the
local DL-identifier and associated DLS-provider resources.
The DLS-user may not delete a queue that is still associated with a DLSAP.
5.6.2.2 Status
This parameter allows the DLS-user to determine whether the requested DLS was provided
successfully or failed for the reason specified. The value conveyed in this parameter is as
follows:
a) “success”;
b) “failure — resource in use”; or
c) “failure — reason unspecified”.
NOTE  Addition to, or refinement of, this list of values to convey more specific diagnostic and management
information is permitted.
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5.7 Bind
5.7.1 Function
The bind DLSAP-address DLS primitive is used
a) to associate a DLSAP-address with the DLSAP at which the primitive is invoked;
b) to associate previously created limited depth FIFO queues with the various priorities and
directions of potential data transfer at the specified DLSAP-address; and
c) to specify values for some Quality of Service (QoS) attributes for connectionless data
transfer services using the s
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