TTCN是一种主要用于测试通信协议和web服务的编程语言。TTCN测试套由许多使用TTCN编写的测试用例构成。

TTCN经常和ASN.1一起使用。

• TTCN-1：第一版，未广泛使用。

• TTCN-2：第二版，对TTCN-1做小修改，广泛应用。主要应用于通信领域的协议一致性测试。

• TTCN-3：最新版本的TTCN，易用性等有改进。该版本适用于各种类型的黑盒测试，而不仅仅局限于通信领域。

TTCN is a programming language used for testing of communication protocols and web services. A TTCN test suite consists of many test cases 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 is more flexible than TTCN-2 in that it can be used for protocol testing as well as testing traditional software.