EN 61158-4-1:2008

SLOVENSKI STANDARD
01-junij-2008
1DGRPHãþD
SIST EN 61158-4:2004
Industrijska komunikacijska omrežja - Specifikacije za procesna vodila - 4-1. del:
Specifikacija protokola na nivoju podatkovnih povezav - Elementi tipa 1 (IEC 61158
-4-1:2007)
Industrial communication networks - Fieldbus specifications -- Part 4-1: Data-link layer
protocol specification - Type 1 elements
Industrielle Kommunikationsnetze - Feldbusse - Teil 4-1: Protokollspezifikation des Data
Link Layer (Sicherungsschicht) - Typ 1-Elemente
Réseaux de communication industriels - Spécifications des bus de terrain - Partie 4-1:
Spécification des protocoles des couches de liaison de données - Eléments de type 1
Ta slovenski standard je istoveten z: EN 61158-4-1:2008
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 61158-4-1
NORME EUROPÉENNE
February 2008
EUROPÄISCHE NORM
ICS 35.100.20; 25.040.40 Partially supersedes EN 61158-4:2004

English version
Industrial communication networks -
Fieldbus specifications -
Part 4-1: Data-link layer protocol specification -
Type 1 elements
(IEC 61158-4-1:2007)
Réseaux de communication industriels -  Industrielle Kommunikationsnetze -
Spécifications des bus de terrain - Feldbusse -
Partie 4-1: Spécification des protocoles Teil 4-1: Protokollspezifikation des
des couches de liaison de données - Data Link Layer (Sicherungsschicht) -
Eléments de type 1 Typ 1-Elemente
(CEI 61158-4-1:2007) (IEC 61158-4-1:2007)

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 61158-4-1:2008 E
Foreword
The text of document 65C/474/FDIS, future edition 1 of IEC 61158-4-1, 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 61158-4-1 on 2008-02-01.
This and the other parts of the EN 61158-4 series supersede EN 61158-4:2004.
With respect to EN 61158-4:2004 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 4-1, 4-2, …, 4-19.
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.
IEC and CENELEC draw 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 1 time synchronization and possibly other types:
JP Hei4-35096 [YC] Communication control method
IEC and CENELEC take 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:
[YC]: Jun-ichi Tsuboi, Mr.
Yamatake Corporation
Shibuyaku Shibuya, 2-12-19
Tohtate International Building
150-8316 Tokyo
Japan
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 and CENELEC shall not be held responsible for identifying any or all such patent rights.
Annex ZA has been added by CENELEC.
__________
- 3 - EN 61158-4-1:2008
Endorsement notice
The text of the International Standard IEC 61158-4-1:2007 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 61158-5-1 NOTE  Harmonized as EN 61158-5-1:2008 (not modified).
IEC 61158-6-1 NOTE  Harmonized as EN 61158-6-1:2008 (not modified).
IEC 61784-1 NOTE  Harmonized as EN 61784-1:2008 (not modified).
ISO 9314-2 NOTE  Harmonized as EN 29314-2:1993 (not modified).
ISO/IEC 9646-1 NOTE  Harmonized as EN ISO/IEC 9646-1:1996 (not modified).
ISO/IEC 9646-2 NOTE  Harmonized as EN ISO/IEC 9646-2:1996 (not modified).
__________
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

IEC 61158-2 2007 Industrial communication networks - EN 61158-2 2008
Fieldbus specifications -
Part 2: Physical layer specification and service
definition
1) 2)
IEC 61158-3-1 - Industrial communication networks - EN 61158-3-1 2008
Fieldbus specifications -
Part 3-1: Data-link layer service definition -
Type 1 elements
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 10038 1993 Information technology - Telecommunications - -
and information exchange between systems -
Local area networks - Media Access Control
(MAC) bridges
1)
ISO/IEC 10731 - Information technology - Open Systems - -
Interconnection - Basic reference model -
Conventions for the definition of OSI services

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

IEC 61158-4-1
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 4-1: Data-link layer protocol specification – Type 1 elements
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XP
ICS 35.100.20; 25.040.40 ISBN 2-8318-9425-5

– 2 – 61158-4-1 © IEC:2007(E)
CONTENTS
FOREWORD.9
0 Introduction .11
0.1 General .11
0.2 Nomenclature for references within this standard .11
1 Scope.12
1.1 General .12
1.2 Specifications.12
1.3 Procedures.12
1.4 Applicability.13
1.5 Conformance.13
2 Normative references .13
3 Terms, definitions, symbols and abbreviations.13
3.1 Reference model terms and definitions.13
3.2 Service convention terms and definitions.15
3.3 Terms and definitions .16
3.4 Symbols and abbreviations.25
4 Overview of the DL-protocol .29
4.1 Three-level model of the DLL .29
4.2 Service provided by the DLL.31
4.3 Structure and definition of DL-addresses.38
4.4 Service assumed from the PhL .51
4.5 Functions of the DLL .54
4.6 Functional classes.56
4.7 Local parameters, variables, counters, timers and queues.58
5 General structure and encoding of PhIDUs and DLPDUs, and related elements of
procedure.72
5.1 PhIDU structure and encoding.72
5.2 Common DLPDU structure, encoding and elements of procedure .72
6 DLPDU-specific structure, encoding and elements of procedure.83
6.1 Establish connection (EC) DLPDU.85
6.2 Disconnect connection (DC) DLPDU.87
6.3 Reset connection (RC) DLPDU.89
6.4 Compel acknowledgement (CA) DLPDU .91
6.5 Compel data (CD) DLPDU .98
6.6 Exchange data (ED) DLPDU.105
6.7 Data (DT) DLPDU.114
6.8 Status response (SR) DLPDU.121
6.9 Compel time (CT) DLPDU .124
6.10 Time distribution (TD) DLPDU .126
6.11 Round-trip-delay query (RQ) DLPDU .128
6.12 Round-trip-delay reply (RR) DLPDU .130
6.13 Probe node DL-address (PN) DLPDU .132
6.14 Probe response (PR) DLPDU .134
6.15 Pass token (PT) DLPDU .136
6.16 Execute sequence (ES) DLPDU .145
6.17 Return token (RT) DLPDU .151

61158-4-1 © IEC:2007(E) – 3 –
6.18 Request interval (RI) DLPDU.153
6.19 Claim LAS (CL) DLPDU.154
6.20 Transfer LAS (TL) DLPDU .156
6.21 Wakeup (WK) DLPDU .159
6.22 Idle (IDLE) DLPDU .161
6.23 Spare DLPDUs .162
6.24 Reserved (not to be used) DLPDUs.163
7 DLPDU-parameter structure and encoding.164
7.1 Structure and encoding of EC-PARAMETERS .164
7.2 Structure and encoding of DC-PARAMETERS .169
7.3 Structure and encoding of RC-PARAMETERS .170
7.4 Structure and encoding of SD-Parameters.172
7.5 Structure and encoding of SR-parameters .179
7.6 Structure and encoding of TD-parameters .180
7.7 Structure and encoding of RQ-parameters.183
7.8 Structure and encoding of RR-parameters.183
7.9 Structure and encoding of PN-parameters .184
7.10 Structure and encoding of DD-parameters.186
8 DL-service elements of procedure .186
8.1 Operation of the DL(SAP)-address, buffer and queue management services . 187
8.2 Operation of the connection-mode services .191
8.3 Operation of the connectionless-mode services.232
8.4 Operation of the scheduling guidance services.243
9 DL-support subprotocol .253
9.1 Scope.253
9.2 Overview of LAS operation .253
9.3 DL-support subprotocol definition .254
9.4 Elements of Procedures for receiving SPDUs . 287
10 Other DLE elements of procedure. 288
10.1 DLE initialization .289
10.2 LAS behavior and operation .293
10.3 DL-support operation.299
10.4 DL-bridge elements of procedure and bridge sub-protocol. 305
10.5 DL-management-information .335
10.6 Implementation profiles .339
11 PICS proforma.345
11.1 Introduction .345
11.2 Scope.345
11.3 Normative references .345
11.4 Definitions .345
11.5 Abbreviations .345
11.6 Conformance.346
11.7 Instructions .346
11.8 Identification.346
11.9 Implementation profile .347
11.10 Major low-level capabilities.351
11.11 Major high-level capabilities .365
Annex A (informative) – Exemplary FCS implementation.376

– 4 – 61158-4-1 © IEC:2007(E)
Annex B (informative) – Type 1: Formal protocol finite state machines. 378
B.1 Basic reception and transmission FSMs .378
B.2 FSMs for DLCs.389
B.3 FSMs for scheduling.395
B.4 FSMs for bridges .395
Annex C (informative) – Type 1: DLPDU and DL-addressing short-form summaries .397
C.1 Fields used in short-form summaries .397
C.2 DLPDU short-form summary grouped by function .399
C.3 DLPDU short-form summary in alphabetic order of DLPDU names .401
C.4 DLPDU short-form summary in alphabetic order of DLPDU acronyms.402
C.5 DLPDU FC code-point assignment matrix – overview and detail . 403
C.6 SD-parameters (status and data-description parameters) of CA, CD, ED and
DT DLPDUs.406
C.7 EC parameters of EC DLPDUs .409
C.8 Parameters of DC and RC DLPDUs.411
C.9 Parameters of TD, RQ and RR DLPDUs .413
C.10 Parameters of PN, PT, ES and RI DLPDUs .415
C.11 Addressing summary extracted from figures and tables of 4.3 . 417
Bibliography.421
INDEX .422
Figure 1 – Relationships of DLSAPs, DLSAP-addresses, DLCEPs, DLCEP-addresses,
DLSEP-addresses and group DL-addresses .19
Figure 2 – Basic structure of a DL-address .38
Figure 3 – Basic structure of a sublink selector.39
Figure 4 – DL-address alternative structures.39
Figure 5 – Basic structure of MAC-addresses .51
Figure 6 – Representation of a DL-address as a MAC-address .51
Figure 7 – Linear relationships of sending and receiving DLCEP sequence-number
variables.63
Figure 8 – DL-address alternative structures.75
Figure 9 – SHORT DL-address field – alternative implicit structures.75
Figure 10 – NODE DL-address field – implicit structure .76
Figure 11 – State transition diagram for a DLCEP.191
Figure 12 – Projection of the sending and receiving DLCEP sequence-number
variables of Figure 7 onto the cyclic sequence-number parameters of CA, CD, DT, ED
and RC DLPDUs, with consequent determination of required actions.208
Figure 13 – State transitions of a DLE .289
Figure 14 – Bridged network topology.306
Figure 15 – Spanning tree representation .306
Figure 16 – DLSDU transit delay, DLPDU lifetime and bridge forwarding delay. 311
Figure 17 – Forwarding and delivering a received DLPDU . 315
Figure 18 – Forwarding a locally-originated DLPDU . 315
Figure 19 – Republishing a DLSDU received from another link .316
Figure 20 – Bridge architecture.318
Figure 21 – Replacement for [IL] Fig 3-2  Bridge ports .327
Figure 22 – Replacement for [IL] Fig 3-3  Bridge architecture . 327

61158-4-1 © IEC:2007(E) – 5 –
Figure A.1 – Example of FCS generation .376
Figure A.2 – Example of FCS syndrome checking on reception. 376
Figure B.1 – Gross structure of FC code points.403
Figure B.2 [Figure 2] – Basic structure of a DL-address .417
Figure B.3 [Figure 3] – Basic structure of a sublink selector. 417
Figure B.4 [Figure 4] – DL-address alternative structures .417
Figure B.5 [Figure 5] – Basic structure of MAC-addresses .417
Figure B.6 [Figure 6] – Representation of a DL-address as a MAC-address .417
Table 1 – Link || node || selector addressing .42
Table 2 – Link-local node || selector addressing.44
Table 3 – Link-local node designators.46
Table 4 – Node-local selector addressing .48
Table 5 – Predefined flat non-local DL-addresses .49
Table 6 – Predefined flat link-local DL-addresses .50
Table 7 – Predefined node-local DL-addresses .50
Table 8 – Correlation of DLPDUs with functional classes .56
Table 9 – FCS length, polynomial and expected residual .77
Table 10 – Summary structure of DLPDUs .84
Table 11 – DLPDU restrictions based on dominant token.85
Table 12 – Structure of EC DLPDUs .85
Table 13 – Structure of DC DLPDUs .88
Table 14 – Structure of RC DLPDUs .90
Table 15 – Structure of CA DLPDUs .92
Table 16 – Structure of CD DLPDUs .98
Table 17 – Structure of ED DLPDUs .106
Table 18 – Structure of DT DLPDUs .114
Table 19 – Structure of SR DLPDUs .122
Table 20 – Structure of CT DLPDUs .124
Table 21 – Structure of TD DLPDUs .126
Table 22 – Structure of RQ DLPDUs .128
Table 23 – Structure of RR DLPDUs .130
Table 24 – Structure of PN DLPDUs .132
Table 25 – Structure of PR DLPDUs .135
Table 26 – Structure of PT DLPDUs.136
Table 27 – Structure of ES DLPDUs .145
Table 28 – Structure of RT DLPDUs .151
Table 29 – Structure of RI DLPDUs.153
Table 30 – Structure of CL DLPDUs.154
Table 31 – Structure of TL DLPDUs .156
Table 32 – Structure of WK DLPDUs.159
Table 33 – Structure of IDLE DLPDUs.161
Table 34 – Assumed structure of undefined (spare) DLPDUs .162

– 6 – 61158-4-1 © IEC:2007(E)
Table 35 – Assumed structure of RESERVED (NOT TO BE USED) DLPDUs .164
Table 36 – Structure of an EC DLPDU’s parameters .165
Table 37 – EC-parameters: 1st octet.165
Table 38 – EC-parameters: 2nd octet.165
Table 39 – EC-parameters: 3rd and 4th octets .166
Table 40 – EC-parameters: 5th and 6th octets .166
Table 41 – EC-parameters: 7th octet .167
Table 42 – EC-parameters: 8th octet .167
Table 43 – EC-parameters: 9th and 10th octets .168
Table 44 – EC-parameters: 11th octet.168
Table 45 – EC-parameters: 12th octet.169
Table 46 – EC-parameters: 13th and 14th octets .169
Table 47 – DC-parameters and RC-parameters: 1st octet . 169
Table 48 – DC-parameters and RC-parameters: 2nd octet . 170
Table 49 – Disconnect reasons .171
Table 50 – Reset reasons .172
Table 51 – RC-parameters: 3rd octet .172
Table 52 – RC-parameters: 4th octet .172
Table 53 – Structure of connectionless-mode CA, CD, DT and ED DLPDUs.173
Table 54 – Short format SD-parameters for connectionless transaction initiators . 174
Table 55 – Short format SD-parameters for connectionless responders . 174
Table 56 – Reply status for unitdata-acknowledgment and exchange-unitdata-reply DT
DLPDUs.175
Table 57 – Structure of connection-oriented CA, CD, DT and ED DLPDUs.177
Table 58 – Short format SD-parameters for DLCEP state.178
Table 59 – Long format SD-parameters for DLCEP state: 1st octet . 178
Table 60 – Long format SD-parameters for DLCEP state: 2nd octet . 178
Table 61 – Long format SD-parameters for DLCEP state: 3rd octet. 179
Table 62 – Reply status for SR DLPDUs .180
Table 63 – Short format SR-parameters.180
Table 64 – Structure of TD-parameters .181
Table 65 – Structure and encoding of the DL-time-quality measures .181
Table 66 – Approximate numeric significance of the bits of seven-octet DL-time .182
Table 67 – Approximate numeric significance of the bits of three-octet short time . 183
Table 68 – Structure of RQ-parameters .183
Table 69 – Structure of RR-parameters.184
Table 70 – Structure and encoding of the RR-time-quality measures .184
Table 71 – Structure of PN-parameters.185
Table 72 – PN-parameters: 1st octet.185
Table 73 – PN-parameters: 2nd octet.185
Table 74 – PN-parameters: 3rd and 4th octets .186
Table 75 – PN-parameters: 5th octet .186
Table 76 – PN-parameters: 6th octet .186

61158-4-1 © IEC:2007(E) – 7 –
Table 77 – Structure of DD-parameters.186
Table 78 – Components of returned DL-time. 244
Table 79 – Time synchronization computation.246
Table 80 – SPDU 1st octet: SPDU class, and protocol version or subclass .254
Table 81 – Probe-response SPDU .255
Table 82 – DL-protocol versions supported .255
Table 83 – PR-SPDU: 3rd and 4th octets .256
Table 84 – Node-activation SPDU.257
Table 85 – Node-activation SPDU: 4th octet .257
Table 86 – LAS-data-base-status SPDU .258
Table 87 – LAS-data-base-status SPDU: 2nd octet .258
Table 88 – Live-list- change SPDU .259
Table 89 – DLE-status structure.259
Table 90 – Live-list-detail SPDU .260
Table 91 – DL-conformance-reply SPDU.261
Table 92 – DL-protocol versions supported .261
Table 93 – DL-conformance encoding (portion 1).262
Table 94 – DL-conformance encoding (portion 2).262
Table 95 – DL-conformance encoding (portion 3).262
Table 96 – DL-conformance encoding (portion 4).263
Table 97 – Link-basic-parameters-reply SPDU.263
Table 98 – Link-master-parameters-reply SPDU .264
Table 99 – Token-hold-time-request SPDU .265
Table 100 – Token-hold-time-array SPDU.266
Table 101 – Sequence element header encoding.268
Table 102 – SHORT DL-address and duration sequence element .268
Table 103 – LONG DL-address and duration sequence element .269
Table 104 – Wakeup request sequence element . 269
Table 105 – Schedule-request SPDU.270
Table 106 – Sequence type, schedule type and priority encoding . 270
Table 107 – Scheduling-completed SPDU.272
Table 108 – Status and reason codes .272
Table 109 – Cancel-schedule SPDU .273
Table 110 – Schedule-cancelled SPDU.273
Table 111 – Link-schedule .274
Table 112 – Schedule-summary SPDU .275
Table 113 – Subschedule-SPDU reference .276
Table 114 – Subschedule SPDU .276
Table 115 – Sequence Sub-SPDU .277
Table 116 – Element-description.278
Table 117 – Schedule-summary-request SPDU.279
Table 118 – Subschedule-request SPDU .279
Table 119 – Parameter-list element-header encoding .280

– 8 – 61158-4-1 © IEC:2007(E)
Table 120 – Begin/end-of-list element.280
Table 121 – Continuation-of-list element.280
Table 122 – SHORT DL-address list element .281
Table 123 – LONG DL-address element .281
Table 124 – DLSAP-address-characteristics element.282
Table 125 – DLCEP-characteristics element .282
Table 126 – Address-query SPDU .283
Table 127 – Address-report SPDU .284
Table 128 – Address-list-query SPDU.285
Table 129 – DL-address selection criteria .285
Table 130 – Address-list-reply SPDU .287
Table 131 – Topology change notification BPDU format.334
Table 132 – Configuration BPDU format .334
Table 133 – Maximum permitted phase-tracking error in a DLE’s sense of DL-time at
the minimum requireable Time Distribution period. 343
Table B.1 – Generic assignment of FC code points.404
Table B.2 – Individual assignment of FC code points .405
Table B.3 – Reply status for SR DLPDUs.408
Table B.4 – Reply status for unitdata-acknowledgment and exchange-unitdata-reply DT
DLPDUs.409
Table B.5 – Approximate numeric significance of the bits of seven-octet DL-time.414
Table B.6 – Approximate numeric significance of the bits of N(NT), A…A, and three-
octet C(NT).414
Table B.7 [Table 1] – Link || node || selector addressing .418
Table B.8 [Table 2] – Link-local node || selector addressing. 418
Table B.9 [Table 5] – Predefined flat non-local DL-addresses .419
Table B.10 [Table 6] – Predefined flat link-local DL-addresses.419
Table B.11 [Table 3] – Link-local node designators .420
Table B.12 [Table 4] – Node-local selector addressing. 420
Table B.13 [Table 7]– Predefined node-local DL-addresses .420

61158-4-1 © IEC:2007(E) – 9 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 4-1: Data-link layer protocol specification – Type 1 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
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in the subject dealt with may participate in this preparatory work. International, governmental and non-
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with the International Orga
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