SIST ES 201 873-1 V4.14.1:2022

• Abstract:

  The present document defines the Core Language of TTCN-3. TTCN-3 can be used for the specification of all types of ; reactive system tests over a variety of communication ports. Typical areas of application are protocol testing (including ; mobile and Internet protocols), service testing (including supplementary services), module testing, testing of CORBA®; based platforms, APIs, etc. TTCN-3 is not restricted to conformance testing and can be used for many other kinds of ; testing including interoperability, robustness, regression, system and integration testing. The specification of test suites ; for physical layer protocols is outside the scope of the present document. ; TTCN-3 is intended to be used for the specification of test suites which are independent of test methods, layers and ; protocols. In addition to the textual format defined in the present document, while GFT (ETSI ES 201 873-3 [i.2]) ; defines a graphical presentation format for TTCN-3. The specification of these formats is outside the scope of the ; present document. ; While the design of TTCN-3 has taken the eventual implementation of TTCN-3 translators and compilers into ; consideration the means of realization of Executable Test Suites (ETS) from Abstract Test Suites (ATS) is outside the ; scope of the present document.

• Status: Published
• Publication Date: 16-May-2022
• ICS: 33.040.01 - Telecommunication systems in general
• ICS: 35.060 - Languages used in information technology
• Technical Committee: SPN - Services and Protocols for Networks
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 09-May-2022
• Due Date: 14-Jul-2022
• Completion Date: 17-May-2022
• Ref Project: ETSI ES 201 873-1 V4.14.1 (2022-05) - Methods for Testing and Specification (MTS); The Testing and Test Control Notation version 3; Part 1: TTCN-3 Core Language

Overview

SIST ES 201 873-1 V4.14.1:2022 specifies the Core Language of TTCN-3 (Testing and Test Control Notation version 3). It is standardized by SIST and aligns with the European standard ETSI ES 201 873-1. The TTCN-3 core language is designed for the specification of test suites for all types of reactive systems, supporting a variety of communication ports and system interfaces.

TTCN-3 is highly flexible and can be used for many testing methodologies, such as protocol conformance, service testing, module testing, API testing, and system integration testing. The language is independent of specific test methods, layers, or protocols, allowing standardized and reusable test suite specifications.

Key Topics

• TTCN-3 Core Language Basics

  • Syntax rules, identifiers, keywords, and module structures.
  • Type system: basic types (such as integer, float, string), structured types (records, sets, arrays, enumerations), and user-defined types.
  • Scope rules for variables, parameters, and language elements.

• Data Handling and Test Logic

  • Expression handling: arithmetic, logical, relational, and bitwise operators.
  • Template mechanism for messages and parameters, supporting matching and value extraction.
  • Variables, constants, timers, and message declarations for defining test scenarios.

• Organizing Test Suites

  • Modular architecture for reusable test definitions.
  • Importing and exporting definitions between modules, supporting scalable test suite construction.
  • Definitions of port types, component types, and communication mechanisms for modeling complex test configurations.

• Control Flow and Test Procedures

  • Support for functions, alternative steps (altsteps), and test cases.
  • Control statements: assignments, conditional branches, loops, and exception handling.
  • Statements for logging, program flow control, and execution management.

Applications

TTCN-3 is utilized across industries for formalizing and automating test cases, offering these practical applications:

• Protocol Testing: Widely used for conformance and interoperability testing of wired, wireless, and internet protocols, including mobile communications.
• Service and API Testing: Effective for testing web services, supplementary telecommunications services, and API standards in IT and telecom environments.
• Module and Integration Testing: Suited for verifying individual software modules or entire systems, supporting integration and regression testing pipelines.
• Distributed and Reactive Systems: Applicable in testing CORBA®-based platforms, network devices, and systems requiring multiple communication interfaces.
• Robustness and Regression Testing: TTCN-3's flexibility enables designing test suites that target system robustness and support ongoing validation in CI/CD processes.

Related Standards

• ETSI ES 201 873 Series: The core document is part of a larger framework. Additional parts (such as graphical presentation format in ETSI ES 201 873-3) complement the core language with tools and notations.
• ISO/IEC 9646 / ETSI EN 300 406: Standards for system and protocol conformance testing that often use TTCN(-3) for test case specification.
• GFT (Graphical Format for TTCN-3): Defined in ETSI ES 201 873-3, providing a graphical representation compatible with the TTCN-3 core language.
• CORBA and API Testing Standards: TTCN-3 aligns closely with standards in software component interoperability and service-oriented architecture (SOA) verification.

Conclusion

SIST ES 201 873-1 V4.14.1:2022 provides a strong, standardized foundation for specifying automated and maintainable test suites using the TTCN-3 core language. By abstracting away implementation specifics and focusing on reusability and modularity, organizations ensure high-quality, repeatable testing for a wide spectrum of communication and IT systems, aligning with international best practices in software and protocol conformance testing.

Final draft ETSI ES 201 873-1 V4.14.1 (2022-03)

ETSI STANDARD
Methods for Testing and Specification (MTS);
The Testing and Test Control Notation version 3;
Part 1: TTCN-3 Core Language
2 Final draft ETSI ES 201 873-1 V4.14.1 (2022-03)

Reference
RES/MTS-201873-1v4.14.1
Keywords
language, methodology, testing, TTCN-3

ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: [phone]  Fax: [phone]

Siret N° 348 623 562 00017 - APE 7112B
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° w061004871

Important notice
The present document can be downloaded from:
http://www.etsi.org/standards-search
The present document may be made available in electronic versions and/or in print. The content of any electronic and/or
print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any
existing or perceived difference in contents between such versions and/or in print, the prevailing version of an ETSI
deliverable is the one made publicly available in PDF format at www.etsi.org/deliver.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
https://portal.etsi.org/TB/ETSIDeliverableStatus.aspx
If you find errors in the present document, please send your comment to one of the following services:
https://portal.etsi.org/People/CommiteeSupportStaff.aspx
Notice of disclaimer & limitation of liability
The information provided in the present deliverable is directed solely to professionals who have the appropriate degree of
experience to understand and interpret its content in accordance with generally accepted engineering or
other professional standard and applicable regulations.
No recommendation as to products and services or vendors is made or should be implied.
No representation or warranty is made that this deliverable is technically accurate or sufficient or conforms to any law
and/or governmental rule and/or regulation and further, no representation or warranty is made of merchantability or fitness
for any particular purpose or against infringement of intellectual property rights.
In no event shall ETSI be held liable for loss of profits or any other incidental or consequential damages.

Any software contained in this deliverable is provided "AS IS" with no warranties, express or implied, including but not
limited to, the warranties of merchantability, fitness for a particular purpose and non-infringement of intellectual property
rights and ETSI shall not be held liable in any event for any damages whatsoever (including, without limitation, damages
for loss of profits, business interruption, loss of information, or any other pecuniary loss) arising out of or related to the use
of or inability to use the software.
Copyright Notification
No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm except as authorized by written permission of ETSI.
The content of the PDF version shall not be modified without the written authorization of ETSI.
The copyright and the foregoing restriction extend to reproduction in all media.

© ETSI 2022.
All rights reserved.
ETSI
3 Final draft ETSI ES 201 873-1 V4.14.1 (2022-03)
Contents
Intellectual Property Rights . 13
Foreword . 13
Modal verbs terminology . 14
1 Scope . 15
2 References . 15
2.1 Normative references . 15
2.2 Informative references . 15
3 Definition of terms, symbols and abbreviations . 17
3.1 Terms . 17
3.2 Symbols . 23
3.3 Abbreviations . 23
4 Introduction . 24
4.0 General . 24
4.1 The core language and presentation formats . 25
4.2 Unanimity of the specification . 26
4.3 Conformance . 26
5 Basic language elements . 26
5.0 General . 26
5.1 Identifiers and keywords . 27
5.2 Scope rules . 28
5.2.0 General . 28
5.2.1 Scope of formal parameters . 30
5.2.2 Uniqueness of identifiers . 30
5.3 Ordering of language elements . 31
5.4 Parameterization . 31
5.4.0 General . 31
5.4.1 Formal parameters . 32
5.4.1.0 General . 32
5.4.1.1 Formal parameters of kind value . 32
5.4.1.2 Formal parameters of kind template . 35
5.4.2 Actual parameters . 37
5.5 Cyclic Definitions. 42
6 Types and values . 43
6.0 General . 43
6.1 Basic types and values . 44
6.1.0 Simple basic types and values. 44
6.1.1 Basic string types and values . 45
6.1.1.0 General . 45
6.1.1.1 Accessing individual string elements . 47
6.1.2 Subtyping of basic types . 48
6.1.2.0 General . 48
6.1.2.1 Lists of templates . 48
6.1.2.2 Lists of types . 48
6.1.2.3 Ranges . 49
6.1.2.4 String length restrictions . 49
6.1.2.5 Pattern subtyping of character string types . 50
6.1.2.6 Mixing subtyping mechanisms . 50
6.1.2.6.1 Mixing patterns, lists and ranges . 50
6.1.2.6.2 Using length restriction with other constraints . 51
6.2 Structured types and values . 51
6.2.0 General . 51
6.2.1 Record type and values . 53
6.2.1.0 General . 53
ETSI
4 Final draft ETSI ES 201 873-1 V4.14.1 (2022-03)
6.2.1.1 Referencing fields of a record type . 56
6.2.1.2 Optional elements in a record. 57
6.2.1.3 Nested type definitions for field types . 57
6.2.2 Set type and values . 58
6.2.2.0 General . 58
6.2.2.1 Referencing fields of a set type . 58
6.2.2.2 Optional elements in a set . 58
6.2.2.3 Nested type definition for field types . 58
6.2.3 Records and sets of single types . 58
6.2.3.0 General . 58
6.2.3.1 Nested type definitions . 61
6.2.3.2 Referencing elements of record of and set of types . 61
6.2.4 Enumerated type and values . 62
6.2.5 Unions . 64
6.2.5.0 General . 64
6.2.5.1 Referencing fields of a union type . 65
6.2.5.2 Option and union . 66
6.2.5.3 Nested type definition for field types . 67
6.2.6 The anytype . 67
6.2.7 Arrays . 67
6.2.8 The default type . 69
6.2.9 Communication port types . 69
6.2.10 Component types . 71
6.2.10.1 Component type definition . 71
6.2.10.2 Reuse of component types . 72
6.2.11 Component references . 74
6.2.12 Addressing entities inside the SUT . 76
6.2.13 Subtyping of structured types . 78
6.2.13.0 General . 78
6.2.13.1 Length subtyping of record ofs and set ofs . 78
6.2.13.2 List subtyping of structured types and anytype . 79
6.2.13.3 Subtyping of the iterated type of record ofs and set ofs . 82
6.2.13.4 Mixing subtyping mechanisms . 83
6.2.14 The timer type . 83
6.2.15 Map types . 83
6.2.15.0 General . 83
6.2.15.1 Map Type Definition . 83
6.2.15.2 Indexed Assignment Notation . 84
6.2.15.3 Unmapping Keys . 84
6.2.15.4 Index Notation . 85
6.2.15.5 Accessing the Keys of a Map . 85
6.2.15.6 Accessing the Values of a Map . 86
6.2.15.7 Referencing of Elements of a Map . 86
6.2.15.8 Nested type definitions . 87
6.2.16 The open type . 87
6.3 Type compatibility . 87
6.3.0 General . 87
6.3.1 Compatibility of non-structured types . 88
6.3.2 Compatibility of structured types . 89
6.3.2.0 General . 89
6.3.2.1 Compatibility of enumerated types . 89
6.3.2.2 Compatibility of record and record of types . 90
6.3.2.3 Compatibility of set and set of types . 91
6.3.2.4 Compatibility of union types . 92
6.3.2.5 Compatibility of anytype types . 93
6.3.2.6 Compatibility between sub-structures . 93
6.3.2.7 Compatibility of the open type . 94
6.3.3 Compatibility of component types . 94
6.3.4 Type compatibility of communication and connection operations . 95
6.3.5 Type conversion . 95
6.3.6 Type compatibility of port types . 95
6.3.7 Type compatibility of timer types . 95
ETSI
5 Final draft ETSI ES 201 873-1 V4.14.1 (2022-03)
6.3.8 Type Compatibility of Map Types . 95
6.4 Type synonym . 96
7 Expressions . 96
7.0 General . 96
7.1 Operators . 97
7.1.0 General . 97
7.1.1 Arithmetic operators . 98
7.1.2 List operator . 99
7.1.3 Relational operators . 99
7.1.4 Logical operators . 102
7.1.5 Bitwise operators . 103
7.1.6 Shift operators . 103
7.1.7 Rotate operators . 104
7.1.8 Presence checking operators . 105
7.1.8.0 General . 105
7.1.8.1 The ispresent operator . 105
7.1.8.2 The ischosen operator . 107
7.1.8.3 The isvalue operator . 108
7.1.8.4 The isbound operator. 109
7.2 Field references and list ele me nts . 110
7.3 Decoded field reference . 111
8 Modules . 111
8.0 General . 111
8.1 Definition of a module . 112
8.2 Module definitions part . 113
8.2.0 General . 113
8.2.1 Module parameters . 114
8.2.2 Groups of definitions . 115
8.2.3 Importing from modules . 116
8.2.3.0 General . 116
8.2.3.1 General format of import . 116
8.2.3.2 Importing single definitions . 122
8.2.3.3 Importing groups . 123
8.2.3.4 Importing definitions of the same kind . 124
8.2.3.5 Importing all definitions of a module . 125
8.2.3.6 Import definitions from other TTCN-3 editions and from non-TTCN-3 modules . 126
8.2.3.7 Importing of import statements from TTCN-3 modules . 128
8.2.3.8 Compatibility of language specifications in imports . 129
8.2.4 Definition of friend modules . 129
8.2.5 Visibility of definitions . 130
8.3 Module control part . 131
9 Port types, component types and test configurations . 132
9.0 General . 132
9.1 Communication ports . 133
9.2 Test system interface . 135
10 Declaring constants . 137
11 Declaring variables . 137
11.0 General . 137
11.1 Value variables . 138
11.2 Template variables . 139
12 Declaring timers . 140
13 Declaring messages . 141
14 Declaring procedure signatures . 142
15 Declaring templates . 143
15.0 General . 143
15.1 Declaring message templates . 144
ETSI
6 Final draft ETSI ES 201 873-1 V4.14.1 (2022-03)
15.2 Declaring signature templates . 146
15.3 Global and local templates . 147
15.4 In-line Templates . 148
15.5 Modified templates . 149
15.6 Referencing elements of templates or template fields . 154
15.6.0 General . 154
15.6.1 Referencing individual string elements. 154
15.6.2 Referencing record and set fields . 157
15.6.3 Referencing record of and set of elements . 158
15.6.4 Referencing signature parameters . 161
15.6.5 Referencing union alternatives . 162
15.7 Template matching mechanisms . 163
15.7.0 General . 163
15.7.1 Specific values . 164
15.7.2 Special symbols that can be used instead of values . 165
15.7.3 Special symbols that can be used inside values . 166
15.7.4 Special symbols which describe attributes of values . 166
15.8 Template Restrictions . 167
15.8.1 Explicit restrictions . 167
15.8.2 Implicit restrictions for template fields, alternatives and elements . 170
15.9 Match Operation . 170
15.10 Valueof Operation . 171
15.11 Concatenating templates of string and list types . 172
15.12 The omit operation . 175
15.13 The present operation . 175
15.14 Presentness conversion . 176
15.15 The Value Extraction . 177
16 Functions, altsteps and testcases . 177
16.0 General . 177
16.1 Functions . 177
16.1.0 General . 177
16.1.1 Invoking functions . 180
16.1.2 Predefined functions . 181
16.1.3 External functions . 183
16.1.4 Invoking functions from specific places . 183
16.1.5 Explicit control functions . 185
16.2 Altsteps . 185
16.2.0 General . 185
16.2.1 Invoking altsteps . 187
16.3 Test cases. 189
17 Void . 190
18 Overview of program statements and operations . 190
19 Basic program statements . 192
19.0 General . 192
19.1 Assignments . 193
19.2 The If-else statement . 194
19.3 The Select statements . 195
19.3.1 The Select case statement . 195
19.3.2 The Select union statement . 196
19.4 The For statement . 197
19.5 The While statement . 198
19.6 The Do-while statement . 198
19.7 The Label statement . 198
19.8 The Goto statement . 199
19.9 The Stop execution statement . 200
19.10 The Return statement . 201
19.11 The Log statement . 202
19.12 The Break statement . 203
19.13 The Continue statement . 204
ETSI
7 Final draft ETSI ES 201 873-1 V4.14.1 (2022-03)
19.14 Statement block . 205
20 Statement and operations for alternative behaviours . 205
20.0 General . 205
20.1 The snapshot mechanism . 206
20.2 The Alt statement . 206
20.3 The Repeat statement . 210
20.4 The Interleave statement . 211
20.5 Default Handling . 213
20.5.0 General . 213
20.5.1 The default mechanism . 214
20.5.2 The Activate operation . 214
20.5.3 The Deactivate operation . 216
21 Configuration Operations . 217
21.0 General . 217
21.1 Connection Operations . 218
21.1.0 General . 218
21.1.1 The Connect and Map operations . 218
21.1.2 The Disconnect and Unmap operations . 220
21.2 Test case operations. 222
21.2.0 General . 222
21.2.1 Test case stop operation . 222
21.3 Test Component Operations . 222
21.3.0 General . 222
21.3.1 The Create operation . 223
21.3.2 The Start test component operation . 224
21.3.3 The Stop test behaviour operation . 225
21.3.4 The Kill test component operation . 226
21.3.5 The Alive operation . 227
21.3.6 The Running operation . 228
21.3.7 The Done operation . 229
21.3.8 The Killed operation . 231
21.3.9 Summary of the use of any and all with components . 234
21.3.10 The Call test component behaviour operation . 234
22 Communication operations. 236
22.0 General . 236
22.1 The communication mechanisms . 236
22.1.0 General . 236
22.1.1 Principles of message-based communication. 236
22.1.2 Principles of procedure-based communication . 237
22.1.3 Principles of unicast, multicast and broadcast communication . 237
22.1.4 General format of communication operations .
...

ETSI STANDARD
Methods for Testing and Specification (MTS);
The Testing and Test Control Notation version 3;
Part 1: TTCN-3 Core Language
2 ETSI ES 201 873-1 V4.14.1 (2022-05)

Reference
RES/MTS-201873-1v4.14.1
Keywords
language, methodology, testing, TTCN-3

ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: [phone]  Fax: [phone]

Siret N° 348 623 562 00017 - APE 7112B
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° w061004871

Important notice
The present document can be downloaded from:
http://www.etsi.org/standards-search
The present document may be made available in electronic versions and/or in print. The content of any electronic and/or
print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any
existing or perceived difference in contents between such versions and/or in print, the prevailing version of an ETSI
deliverable is the one made publicly available in PDF format at www.etsi.org/deliver.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
https://portal.etsi.org/TB/ETSIDeliverableStatus.aspx
If you find errors in the present document, please send your comment to one of the following services:
https://portal.etsi.org/People/CommiteeSupportStaff.aspx
If you find a security vulnerability in the present document, please report it through our
Coordinated Vulnerability Disclosure Program:
https://www.etsi.org/standards/coordinated-vulnerability-disclosure
Notice of disclaimer & limitation of liability
The information provided in the present deliverable is directed solely to professionals who have the appropriate degree of
experience to understand and interpret its content in accordance with generally accepted engineering or
other professional standard and applicable regulations.
No recommendation as to products and services or vendors is made or should be implied.
No representation or warranty is made that this deliverable is technically accurate or sufficient or conforms to any law
n or warranty is made of merchantability or fitness
and/or governmental rule and/or regulation and further, no representatio
for any particular purpose or against infringement of intellectual property rights.
In no event shall ETSI be held liable for loss of profits or any other incidental or consequential damages.

Any software contained in this deliverable is provided "AS IS" with no warranties, express or implied, including but not
limited to, the warranties of merchantability, fitness for a particular purpose and non-infringement of intellectual property
rights and ETSI shall not be held liable in any event for any damages whatsoever (including, without limitation, damages
for loss of profits, business interruption, loss of information, or any other pecuniary loss) arising out of or related to the use
of or inability to use the software.
Copyright Notification
No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm except as authorized by written permission of ETSI.
The content of the PDF version shall not be modified without the written authorization of ETSI.
The copyright and the foregoing restriction extend to reproduction in all media.

© ETSI 2022.
All rights reserved.
ETSI
3 ETSI ES 201 873-1 V4.14.1 (2022-05)
Contents
Intellectual Property Rights . 13
Foreword . 13
Modal verbs terminology . 14
1 Scope . 15
2 References . 15
2.1 Normative references . 15
2.2 Informative references . 15
3 Definition of terms, symbols and abbreviations . 17
3.1 Terms . 17
3.2 Symbols . 23
3.3 Abbreviations . 23
4 Introduction . 24
4.0 General . 24
4.1 The core language and presentation formats . 25
4.2 Unanimity of the specification . 26
4.3 Conformance . 26
5 Basic language elements . 27
5.0 General . 27
5.1 Identifiers and keywords . 28
5.2 Scope rules . 28
5.2.0 General . 28
5.2.1 Scope of formal parameters . 30
5.2.2 Uniqueness of identifiers . 30
5.3 Ordering of language elements . 31
5.4 Parameterization . 31
5.4.0 General . 31
5.4.1 Formal parameters . 32
5.4.1.0 General . 32
5.4.1.1 Formal parameters of kind value . 33
5.4.1.2 Formal parameters of kind template . 36
5.4.2 Actual parameters . 38
5.5 Cyclic Definitions. 43
6 Types and values . 44
6.0 General . 44
6.1 Basic types and values . 45
6.1.0 Simple basic types and values. 45
6.1.1 Basic string types and values . 45
6.1.1.0 General . 45
6.1.1.1 Accessing individual string elements . 48
6.1.2 Subtyping of basic types . 48
6.1.2.0 General . 48
6.1.2.1 Lists of templates . 49
6.1.2.2 Lists of types . 49
6.1.2.3 Ranges . 49
6.1.2.4 String length restrictions . 50
6.1.2.5 Pattern subtyping of character string types . 50
6.1.2.6 Mixing subtyping mechanisms . 51
6.1.2.6.1 Mixing patterns, lists and ranges . 51
6.1.2.6.2 Using length restriction with other constraints . 51
6.2 Structured types and values . 52
6.2.0 General . 52
6.2.1 Record type and values . 53
6.2.1.0 General . 53
ETSI
4 ETSI ES 201 873-1 V4.14.1 (2022-05)
6.2.1.1 Referencing fields of a record type . 56
6.2.1.2 Optional elements in a record. 57
6.2.1.3 Nested type definitions for field types . 58
6.2.2 Set type and values . 58
6.2.2.0 General . 58
6.2.2.1 Referencing fields of a set type . 58
6.2.2.2 Optional elements in a set . 58
6.2.2.3 Nested type definition for field types . 59
6.2.3 Records and sets of single types . 59
6.2.3.0 General . 59
6.2.3.1 Nested type definitions . 61
6.2.3.2 Referencing elements of record of and set of types . 62
6.2.4 Enumerated type and values . 62
6.2.5 Unions . 64
6.2.5.0 General . 64
6.2.5.1 Referencing fields of a union type . 66
6.2.5.2 Option and union . 67
6.2.5.3 Nested type definition for field types . 67
6.2.6 The anytype . 67
6.2.7 Arrays . 68
6.2.8 The default type . 69
6.2.9 Communication port types . 70
6.2.10 Component types . 72
6.2.10.1 Component type definition . 72
6.2.10.2 Reuse of component types . 73
6.2.11 Component references . 75
6.2.12 Addressing entities inside the SUT . 77
6.2.13 Subtyping of structured types . 79
6.2.13.0 General . 79
6.2.13.1 Length subtyping of record ofs and set ofs . 79
6.2.13.2 List subtyping of structured types and anytype . 80
6.2.13.3 Subtyping of the iterated type of record ofs and set ofs . 82
6.2.13.4 Mixing subtyping mechanisms . 84
6.2.14 The timer type . 84
6.2.15 Map types . 84
6.2.15.0 General . 84
6.2.15.1 Map Type Definition . 84
6.2.15.2 Indexed Assignment Notation . 84
6.2.15.3 Unmapping Keys . 85
6.2.15.4 Index Notation . 85
6.2.15.5 Accessing the Keys of a Map . 86
6.2.15.6 Accessing the Values of a Map . 86
6.2.15.7 Referencing of Elements of a Map . 87
6.2.15.8 Nested type definitions . 87
6.2.16 The open type . 87
6.3 Type compatibility . 88
6.3.0 General . 88
6.3.1 Compatibility of non-structured types . 88
6.3.2 Compatibility of structured types . 90
6.3.2.0 General . 90
6.3.2.1 Compatibility of enumerated types . 90
6.3.2.2 Compatibility of record and record of types . 91
6.3.2.3 Compatibility of set and set of types . 92
6.3.2.4 Compatibility of union types . 92
6.3.2.5 Compatibility of anytype types . 93
6.3.2.6 Compatibility between sub-structures . 94
6.3.2.7 Compatibility of the open type . 94
6.3.3 Compatibility of component types . 95
6.3.4 Type compatibility of communication and connection operations . 95
6.3.5 Type conversion . 96
6.3.6 Type compatibility of port types . 96
6.3.7 Type compatibility of timer types . 96
ETSI
5 ETSI ES 201 873-1 V4.14.1 (2022-05)
6.3.8 Type Compatibility of Map Types . 96
6.4 Type synonym . 96
7 Expressions . 96
7.0 General . 96
7.1 Operators . 97
7.1.0 General . 97
7.1.1 Arithmetic operators . 99
7.1.2 List operator . 99
7.1.3 Relational operators . 100
7.1.4 Logical operators . 103
7.1.5 Bitwise operators . 103
7.1.6 Shift operators . 104
7.1.7 Rotate operators . 104
7.1.8 Presence checking operators . 105
7.1.8.0 General . 105
7.1.8.1 The ispresent operator . 106
7.1.8.2 The ischosen operator . 107
7.1.8.3 The isvalue operator . 108
7.1.8.4 The isbound operator. 110
7.2 Field references and list ele me nts . 111
7.3 Decoded field reference . 111
8 Modules . 112
8.0 General . 112
8.1 Definition of a module . 112
8.2 Module definitions part . 113
8.2.0 General . 113
8.2.1 Module parameters . 114
8.2.2 Groups of definitions . 115
8.2.3 Importing from modules . 116
8.2.3.0 General . 116
8.2.3.1 General format of import . 116
8.2.3.2 Importing single definitions . 123
8.2.3.3 Importing groups . 124
8.2.3.4 Importing definitions of the same kind . 125
8.2.3.5 Importing all definitions of a module . 125
8.2.3.6 Import definitions from other TTCN-3 editions and from non-TTCN-3 modules . 126
8.2.3.7 Importing of import statements from TTCN-3 modules . 128
8.2.3.8 Compatibility of language specifications in imports . 129
8.2.4 Definition of friend modules . 130
8.2.5 Visibility of definitions . 130
8.3 Module control part . 132
9 Port types, component types and test configurations . 133
9.0 General . 133
9.1 Communication ports . 133
9.2 Test system interface . 136
10 Declaring constants . 138
11 Declaring variables . 138
11.0 General . 138
11.1 Value variables . 139
11.2 Template variables . 140
12 Declaring timers . 141
13 Declaring messages . 142
14 Declaring procedure signatures . 143
15 Declaring templates . 144
15.0 General . 144
15.1 Declaring message templates . 145
ETSI
6 ETSI ES 201 873-1 V4.14.1 (2022-05)
15.2 Declaring signature templates . 147
15.3 Global and local templates . 148
15.4 In-line Templates . 149
15.5 Modified templates . 150
15.6 Referencing elements of templates or template fields . 155
15.6.0 General . 155
15.6.1 Referencing individual string elements. 155
15.6.2 Referencing record and set fields . 158
15.6.3 Referencing record of and set of elements . 159
15.6.4 Referencing signature parameters . 162
15.6.5 Referencing union alternatives . 163
15.7 Template matching mechanisms . 164
15.7.0 General . 164
15.7.1 Specific values . 165
15.7.2 Special symbols that can be used instead of values . 166
15.7.3 Special symbols that can be used inside values . 167
15.7.4 Special symbols which describe attributes of values . 167
15.8 Template Restrictions . 168
15.8.1 Explicit restrictions . 168
15.8.2 Implicit restrictions for template fields, alternatives and elements . 171
15.9 Match Operation . 171
15.10 Valueof Operation . 172
15.11 Concatenating templates of string and list types . 173
15.12 The omit operation . 176
15.13 The present operation . 176
15.14 Presentness conversion . 177
15.15 The Value Extraction . 178
16 Functions, altsteps and testcases . 178
16.0 General . 178
16.1 Functions . 178
16.1.0 General . 178
16.1.1 Invoking functions . 181
16.1.2 Predefined functions . 181
16.1.3 External functions . 184
16.1.4 Invoking functions from specific places . 184
16.1.5 Explicit control functions . 186
16.2 Altsteps . 186
16.2.0 General . 186
16.2.1 Invoking altsteps . 188
16.3 Test cases. 190
17 Void . 191
18 Overview of program statements and operations . 191
19 Basic program statements . 193
19.0 General . 193
19.1 Assignments . 193
19.2 The If-else statement . 195
19.3 The Select statements . 195
19.3.1 The Select case statement . 195
19.3.2 The Select union statement . 197
19.4 The For statement . 198
19.5 The While statement . 198
19.6 The Do-while statement . 199
19.7 The Label statement . 199
19.8 The Goto statement . 200
19.9 The Stop execution statement . 201
19.10 The Return statement . 201
19.11 The Log statement . 202
19.12 The Break statement . 204
19.13 The Continue statement . 204
ETSI
7 ETSI ES 201 873-1 V4.14.1 (2022-05)
19.14 Statement block . 205
20 Statement and operations for alternative behaviours . 205
20.0 General . 205
20.1 The snapshot mechanism . 206
20.2 The Alt statement . 206
20.3 The Repeat statement . 211
20.4 The Interleave statement . 211
20.5 Default Handling . 214
20.5.0 General . 214
20.5.1 The default mechanism . 214
20.5.2 The Activate operation . 214
20.5.3 The Deactivate operation . 216
21 Configuration Operations . 217
21.0 General . 217
21.1 Connection Operations . 218
21.1.0 General . 218
21.1.1 The Connect and Map operations . 218
21.1.2 The Disconnect and Unmap operations . 220
21.2 Test case operations. 222
21.2.0 General . 222
21.2.1 Test case stop operation . 222
21.3 Test Component Operations . 222
21.3.0 General . 222
21.3.1 The Create operation . 223
21.3.2 The Start test component operation . 224
21.3.3 The Stop test behaviour operation . 225
21.3.4 The Kill test component operation . 226
21.3.5 The Alive operation . 227
21.3.6 The Running operation . 228
21.3.7 The Done operation . 229
21.3.8 The Killed operation . 231
21.3.9 Summary of the use of any and all with components . 234
21.3.10 The Call test component behaviour operation . 234
22 Communication operations. 236
22.0 General . 236
22.1 The communication mechanisms . 236
22.1.0 General . 236
22.1.1 Principles of message-based communication. 236
22.1.2 Principles of procedure-based communication . 237
22.1.3 Principles of unicast, multicast and broadcast communication .
...

SLOVENSKI STANDARD
01-julij-2022
Metode za preskušanje in specificiranje (MTS) - 3. različica zapisa preskušanja in
krmiljenja preskusov - 1. del: Jedrni jezik TTCN-3
Methods for Testing and Specification (MTS) - The Testing and Test Control Notation
version 3 - Part 1: TTCN-3 Core Language
Ta slovenski standard je istoveten z: ETSI ES 201 873-1 V4.14.1 (2022-05)
ICS:
33.040.01 Telekomunikacijski sistemi Telecommunication systems
na splošno in general
35.060 Jeziki, ki se uporabljajo v Languages used in
informacijski tehniki in information technology
tehnologiji
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

ETSI STANDARD
Methods for Testing and Specification (MTS);
The Testing and Test Control Notation version 3;
Part 1: TTCN-3 Core Language
2 ETSI ES 201 873-1 V4.14.1 (2022-05)

Reference
RES/MTS-201873-1v4.14.1
Keywords
language, methodology, testing, TTCN-3

ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: [phone]  Fax: [phone]

Siret N° 348 623 562 00017 - APE 7112B
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° w061004871

Important notice
The present document can be downloaded from:
http://www.etsi.org/standards-search
The present document may be made available in electronic versions and/or in print. The content of any electronic and/or
print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any
existing or perceived difference in contents between such versions and/or in print, the prevailing version of an ETSI
deliverable is the one made publicly available in PDF format at www.etsi.org/deliver.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
https://portal.etsi.org/TB/ETSIDeliverableStatus.aspx
If you find errors in the present document, please send your comment to one of the following services:
https://portal.etsi.org/People/CommiteeSupportStaff.aspx
If you find a security vulnerability in the present document, please report it through our
Coordinated Vulnerability Disclosure Program:
https://www.etsi.org/standards/coordinated-vulnerability-disclosure
Notice of disclaimer & limitation of liability
The information provided in the present deliverable is directed solely to professionals who have the appropriate degree of
experience to understand and interpret its content in accordance with generally accepted engineering or
other professional standard and applicable regulations.
No recommendation as to products and services or vendors is made or should be implied.
No representation or warranty is made that this deliverable is technically accurate or sufficient or conforms to any law
n or warranty is made of merchantability or fitness
and/or governmental rule and/or regulation and further, no representatio
for any particular purpose or against infringement of intellectual property rights.
In no event shall ETSI be held liable for loss of profits or any other incidental or consequential damages.

Any software contained in this deliverable is provided "AS IS" with no warranties, express or implied, including but not
limited to, the warranties of merchantability, fitness for a particular purpose and non-infringement of intellectual property
rights and ETSI shall not be held liable in any event for any damages whatsoever (including, without limitation, damages
for loss of profits, business interruption, loss of information, or any other pecuniary loss) arising out of or related to the use
of or inability to use the software.
Copyright Notification
No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm except as authorized by written permission of ETSI.
The content of the PDF version shall not be modified without the written authorization of ETSI.
The copyright and the foregoing restriction extend to reproduction in all media.

© ETSI 2022.
All rights reserved.
ETSI
3 ETSI ES 201 873-1 V4.14.1 (2022-05)
Contents
Intellectual Property Rights . 13
Foreword . 13
Modal verbs terminology . 14
1 Scope . 15
2 References . 15
2.1 Normative references . 15
2.2 Informative references . 15
3 Definition of terms, symbols and abbreviations . 17
3.1 Terms . 17
3.2 Symbols . 23
3.3 Abbreviations . 23
4 Introduction . 24
4.0 General . 24
4.1 The core language and presentation formats . 25
4.2 Unanimity of the specification . 26
4.3 Conformance . 26
5 Basic language elements . 27
5.0 General . 27
5.1 Identifiers and keywords . 28
5.2 Scope rules . 28
5.2.0 General . 28
5.2.1 Scope of formal parameters . 30
5.2.2 Uniqueness of identifiers . 30
5.3 Ordering of language elements . 31
5.4 Parameterization . 31
5.4.0 General . 31
5.4.1 Formal parameters . 32
5.4.1.0 General . 32
5.4.1.1 Formal parameters of kind value . 33
5.4.1.2 Formal parameters of kind template . 36
5.4.2 Actual parameters . 38
5.5 Cyclic Definitions. 43
6 Types and values . 44
6.0 General . 44
6.1 Basic types and values . 45
6.1.0 Simple basic types and values. 45
6.1.1 Basic string types and values . 45
6.1.1.0 General . 45
6.1.1.1 Accessing individual string elements . 48
6.1.2 Subtyping of basic types . 48
6.1.2.0 General . 48
6.1.2.1 Lists of templates . 49
6.1.2.2 Lists of types . 49
6.1.2.3 Ranges . 49
6.1.2.4 String length restrictions . 50
6.1.2.5 Pattern subtyping of character string types . 50
6.1.2.6 Mixing subtyping mechanisms . 51
6.1.2.6.1 Mixing patterns, lists and ranges . 51
6.1.2.6.2 Using length restriction with other constraints . 51
6.2 Structured types and values . 52
6.2.0 General . 52
6.2.1 Record type and values . 53
6.2.1.0 General . 53
ETSI
4 ETSI ES 201 873-1 V4.14.1 (2022-05)
6.2.1.1 Referencing fields of a record type . 56
6.2.1.2 Optional elements in a record. 57
6.2.1.3 Nested type definitions for field types . 58
6.2.2 Set type and values . 58
6.2.2.0 General . 58
6.2.2.1 Referencing fields of a set type . 58
6.2.2.2 Optional elements in a set . 58
6.2.2.3 Nested type definition for field types . 59
6.2.3 Records and sets of single types . 59
6.2.3.0 General . 59
6.2.3.1 Nested type definitions . 61
6.2.3.2 Referencing elements of record of and set of types . 62
6.2.4 Enumerated type and values . 62
6.2.5 Unions . 64
6.2.5.0 General . 64
6.2.5.1 Referencing fields of a union type . 66
6.2.5.2 Option and union . 67
6.2.5.3 Nested type definition for field types . 67
6.2.6 The anytype . 67
6.2.7 Arrays . 68
6.2.8 The default type . 69
6.2.9 Communication port types . 70
6.2.10 Component types . 72
6.2.10.1 Component type definition . 72
6.2.10.2 Reuse of component types . 73
6.2.11 Component references . 75
6.2.12 Addressing entities inside the SUT . 77
6.2.13 Subtyping of structured types . 79
6.2.13.0 General . 79
6.2.13.1 Length subtyping of record ofs and set ofs . 79
6.2.13.2 List subtyping of structured types and anytype . 80
6.2.13.3 Subtyping of the iterated type of record ofs and set ofs . 82
6.2.13.4 Mixing subtyping mechanisms . 84
6.2.14 The timer type . 84
6.2.15 Map types . 84
6.2.15.0 General . 84
6.2.15.1 Map Type Definition . 84
6.2.15.2 Indexed Assignment Notation . 84
6.2.15.3 Unmapping Keys . 85
6.2.15.4 Index Notation . 85
6.2.15.5 Accessing the Keys of a Map . 86
6.2.15.6 Accessing the Values of a Map . 86
6.2.15.7 Referencing of Elements of a Map . 87
6.2.15.8 Nested type definitions . 87
6.2.16 The open type . 87
6.3 Type compatibility . 88
6.3.0 General . 88
6.3.1 Compatibility of non-structured types . 88
6.3.2 Compatibility of structured types . 90
6.3.2.0 General . 90
6.3.2.1 Compatibility of enumerated types . 90
6.3.2.2 Compatibility of record and record of types . 91
6.3.2.3 Compatibility of set and set of types . 92
6.3.2.4 Compatibility of union types . 92
6.3.2.5 Compatibility of anytype types . 93
6.3.2.6 Compatibility between sub-structures . 94
6.3.2.7 Compatibility of the open type . 94
6.3.3 Compatibility of component types . 95
6.3.4 Type compatibility of communication and connection operations . 95
6.3.5 Type conversion . 96
6.3.6 Type compatibility of port types . 96
6.3.7 Type compatibility of timer types . 96
ETSI
5 ETSI ES 201 873-1 V4.14.1 (2022-05)
6.3.8 Type Compatibility of Map Types . 96
6.4 Type synonym . 96
7 Expressions . 96
7.0 General . 96
7.1 Operators . 97
7.1.0 General . 97
7.1.1 Arithmetic operators . 99
7.1.2 List operator . 99
7.1.3 Relational operators . 100
7.1.4 Logical operators . 103
7.1.5 Bitwise operators . 103
7.1.6 Shift operators . 104
7.1.7 Rotate operators . 104
7.1.8 Presence checking operators . 105
7.1.8.0 General . 105
7.1.8.1 The ispresent operator . 106
7.1.8.2 The ischosen operator . 107
7.1.8.3 The isvalue operator . 108
7.1.8.4 The isbound operator. 110
7.2 Field references and list ele me nts . 111
7.3 Decoded field reference . 111
8 Modules . 112
8.0 General . 112
8.1 Definition of a module . 112
8.2 Module definitions part . 113
8.2.0 General . 113
8.2.1 Module parameters . 114
8.2.2 Groups of definitions . 115
8.2.3 Importing from modules . 116
8.2.3.0 General . 116
8.2.3.1 General format of import . 116
8.2.3.2 Importing single definitions . 123
8.2.3.3 Importing groups . 124
8.2.3.4 Importing definitions of the same kind . 125
8.2.3.5 Importing all definitions of a module . 125
8.2.3.6 Import definitions from other TTCN-3 editions and from non-TTCN-3 modules . 126
8.2.3.7 Importing of import statements from TTCN-3 modules . 128
8.2.3.8 Compatibility of language specifications in imports . 129
8.2.4 Definition of friend modules . 130
8.2.5 Visibility of definitions . 130
8.3 Module control part . 132
9 Port types, component types and test configurations . 133
9.0 General . 133
9.1 Communication ports . 133
9.2 Test system interface . 136
10 Declaring constants . 138
11 Declaring variables . 138
11.0 General . 138
11.1 Value variables . 139
11.2 Template variables . 140
12 Declaring timers . 141
13 Declaring messages . 142
14 Declaring procedure signatures . 143
15 Declaring templates . 144
15.0 General . 144
15.1 Declaring message templates . 145
ETSI
6 ETSI ES 201 873-1 V4.14.1 (2022-05)
15.2 Declaring signature templates . 147
15.3 Global and local templates . 148
15.4 In-line Templates . 149
15.5 Modified templates . 150
15.6 Referencing elements of templates or template fields . 155
15.6.0 General . 155
15.6.1 Referencing individual string elements. 155
15.6.2 Referencing record and set fields . 158
15.6.3 Referencing record of and set of elements . 159
15.6.4 Referencing signature parameters . 162
15.6.5 Referencing union alternatives . 163
15.7 Template matching mechanisms . 164
15.7.0 General . 164
15.7.1 Specific values . 165
15.7.2 Special symbols that can be used instead of values . 166
15.7.3 Special symbols that can be used inside values . 167
15.7.4 Special symbols which describe attributes of values . 167
15.8 Template Restrictions . 168
15.8.1 Explicit restrictions . 168
15.8.2 Implicit restrictions for template fields, alternatives and elements . 171
15.9 Match Operation . 171
15.10 Valueof Operation . 172
15.11 Concatenating templates of string and list types . 173
15.12 The omit operation . 176
15.13 The present operation . 176
15.14 Presentness conversion . 177
15.15 The Value Extraction . 178
16 Functions, altsteps and testcases . 178
16.0 General . 178
16.1 Functions . 178
16.1.0 General . 178
16.1.1 Invoking functions . 181
16.1.2 Predefined functions . 181
16.1.3 External functions . 184
16.1.4 Invoking functions from specific places . 184
16.1.5 Explicit control functions . 186
16.2 Altsteps . 186
16.2.0 General . 186
16.2.1 Invoking altsteps . 188
16.3 Test cases. 190
17 Void . 191
18 Overview of program statements and operations . 191
19 Basic program statements . 193
19.0 General . 193
19.1 Assignments . 193
19.2 The If-else statement . 195
19.3 The Select statements . 195
19.3.1 The Select case statement . 195
19.3.2 The Select union statement . 197
19.4 The For statement . 198
19.5 The While statement . 198
19.6 The Do-while statement . 199
19.7 The Label statement . 199
19.8 The Goto statement . 200
19.9 The Stop execution statement . 201
19.10 The Return statement . 201
19.11 The Log statement . 202
19.12 The Break statement . 204
19.13 The Continue statement . 204
ETSI
7 ETSI ES 201 873-1 V4.14.1 (2022-05)
19.14 Statement block . 205
20 Statement and operations for alternative behaviours . 205
20.0 General . 205
20.1 The snapshot mechanism . 206
20.2 The Alt statement . 206
20.3 The Repeat statement . 211
20.4 The Interleave statement . 211
20.5 Default Handling . 214
20.5.0 General . 214
20.5.1 The default mechanism . 214
20.5.2 The Activate operation . 214
20.5.3 The Deactivate operation . 216
21 Configuration Operations . 217
21.0 General . 217
21.1 Connection Operations . 218
21.1.0 General . 218
21.1.1 The Connect and Map operations . 218
21.1.2 The Disconnect and Unmap operations . 220
21.2 Test case operations. 222
21.2.0 General . 222
21.2.1 Test case stop operation . 222
21.3 Test Component Operations . 222
21.3.0 General . 222
21.3.1 The Create operation . 223
21.3.2 The Start test component operation . 224
21.3.3 The Stop test behaviour operation . 225
21.3.4 The Kill test component operation . 226
21.3.5 The Alive operation . 227
21.3.6 The Running operation . 228
21.3.7 The Done operation . 229
21.3.8 The Killed operation . 231
21.3.9 Summary of the use of any and all with components .
...