TTCN was first developed as an international standard as part 3 of the ISO 9646 Methodology and Framework for Conformance Testing. At that time the language was based on a tabular representation and was strongly oriented towards testing the conformance of implementations based on the Open Systems Interconnection architecture, or OSI Reference Model. The first version of TTCN (later to become known as TTCN-1) was published in 1992. TTCN-1 was quickly taken up by the telecoms community, in particular for testing GSM handsets. The second version, TTCN-2, was published a few years later and included new functionality such as parallelism, modularization and better interfacing to ASN.1.
Around this time, ETSI TC MTS recognized that TTCN needed to evolve if it was to meet the growing challenges of rapidly emerging technologies (not least IP). Furthermore, there was a clear need for TTCN to address a variety of testing paradigms such as load, performance and interoperability.
Subsequently, the responsibility for the TTCN standard moved from ISO to ETSI and TTCN-3 was born. While many of the basic testing-specific concepts were retained, TTCN-3 improved on its predecessors through a complete re-definition of the syntax to make it closer to a regular programming language and with a much wider scope of testing.
TTCN-3 was launched in October 2000 and since then its flexibility and adaptability has led to its world-wide deployment in many domains, including transportation, internet, web-based services and distributed systems.
