TTCN is a

programming language A programming language is a system of notation for writing computer programs. Programming languages are described in terms of their Syntax (programming languages), syntax (form) and semantics (computer science), semantics (meaning), usually def ...

used for testing of

communication protocol A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any variation of a physical quantity. The protocol defines the rules, syntax, semantics (computer science), sem ...

s and

web service A web service (WS) is either: * a service offered by an electronic device to another electronic device, communicating with each other via the Internet, or * a server running on a computer device, listening for requests at a particular port over a n ...

s. A TTCN test suite consists of many

test case In software engineering, a test case is a specification of the inputs, execution conditions, testing procedure, and expected results that define a single test to be executed to achieve a particular software testing objective, such as to exercise ...

s written in the TTCN programming language. Until version 2 the language was written in tables and called ''Tree and Tabular Combined Notation''. Reading and editing this language required special TTCN editors. Beginning with version 3 TTCN was renamed to ''Testing and Test Control Notation''. It is now closer to current programming languages and can be edited with traditional editors.

TTCN-3 TTCN-3 ''(Testing and Test Control Notation version 3)'' is a strongly typed testing language used in conformance testing of communicating systems. TTCN-3 is written by ETSI in the ES 201 873 series, and standardized by ITU-T in the Z.160 Series. TT ...

is more flexible than TTCN-2 in that it can be used for protocol testing as well as testing traditional software. All versions of TTCN need dedicated compilers or interpreters for execution. TTCN is widely used, for example;

ETSI The European Telecommunications Standards Institute (ETSI) is an independent, not-for-profit, standardization organization operating in the field of Information and communications technology, information and communications. ETSI supports the de ...

ITU The International Telecommunication Union (ITU)In the other common languages of the ITU: * * is a specialized agency of the United Nations responsible for many matters related to information and communication technologies. It was established ...

for the testing of telecommunication protocols.

Conformance test Conformance is how well something, such as a product, service or a system, meets a specified standard and may refer more specifically to: * Conformance testing Conformance testing and also known as compliance testing or type testing, is testing ...

cases of

standards like

ISDN Integrated Services Digital Network (ISDN) is a set of communication standards for simultaneous digital transmission of voice, video, data, and other network services over the digitalised circuits of the public switched telephone network. ...

DECT Digital Enhanced Cordless Telecommunications (DECT) is a cordless telephony standard maintained by ETSI. It originated in Europe, where it is the common standard, replacing earlier standards, such as CT1 and CT2. Since the DECT-2020 standard ...

GSM The Global System for Mobile Communications (GSM) is a family of standards to describe the protocols for second-generation (2G) digital cellular networks, as used by mobile devices such as mobile phones and Mobile broadband modem, mobile broadba ...

EDGE Edge or EDGE may refer to: Technology Computing * Edge computing, a network load-balancing system * Edge device, an entry point to a computer network * Adobe Edge, a graphical development application * Microsoft Edge, a web browser developed by ...

, 3G,

DSRC Dedicated short-range communications (DSRC) is a technology for direct wireless exchange of vehicle-to-everything (V2X) and other intelligent transportation systems (ITS) data between vehicles, other road users (pedestrians, cyclists, etc.), and ...

have also been written in TTCN. Recently it has also been used for testing various protocol standards e.g.

Bluetooth Bluetooth is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is li ...

, IP. Execution of those

s against products (e.g. phones, mobile phones, service enablers or network elements) is used to verify that the protocol implementation in those products meet the requirements defined by telecommunication standards. TTCN is often combined with

ASN.1 Abstract Syntax Notation One (ASN.1) is a standard interface description language (IDL) for defining data structures that can be serialized and deserialized in a cross-platform way. It is broadly used in telecommunications and computer networ ...

Versions

*TTCN-1: Standardized in 1992 by

ISO The International Organization for Standardization (ISO ; ; ) is an independent, non-governmental, international standard development organization composed of representatives from the national standards organizations of member countries. Me ...

and

CCITT The International Telecommunication Union Telecommunication Standardization Sector (ITU-T) is one of the three Sectors (branches) of the International Telecommunication Union (ITU). It is responsible for coordinating standards for telecommunicat ...

as ISO/IEC 9646-3 and

X.292 for Open Systems Interconnection (OSI) conformance testing methodology and framework. *TTCN-2: Standardized in 1998 by

and

, adding concurrency and multiple modules support to TTCN-1. *

: Written by

and standardized in 2000 by

under reference Z.140. It aimed at being a more generic testing language than TTCN-2. In 2007 the recommendation moved from Z.140 to Z.160.

Background information

Conformance testing Conformance testing and also known as compliance testing or type testing, is testing or other activities that determine whether a process, product, or service complies with the requirements of a specification, technical standard, contract, or reg ...

means a test execution against a well-defined

, e.g. a test written in TTCN. Plug-tests, also called interoperability testing, are test cases executed with a client - server model; e.g. Mail-Client against Mail-server, phone against network, Bluetooth headset against Bluetooth phone. Plug-tests are e.g. often executed at so-called unplug-tests. Conformance-tests and plug-tests complement each other. If properly done, interoperability errors found with plug-tests should lead to definition of new conformance test cases that cover the failed test.

External links

ITU TTCN StudygroupETSI TTCN-3 web site
{{Webarchive, url=https://web.archive.org/web/20080724171957/http://www.ttcn-3.org/ , date=2008-07-24
TTCN-3 Quick Reference Card
ITU-T recommendations