TTCN-3


TTCN-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.
TTCN-3 has its own data types and can be combined with ASN.1, IDL and XML type definitions.

Standard organization

ITU-T TTCN-3 standard is part of the Z Series and is organized in several parts:
The top level container in a test suite is a module. It is usually a file.
A component is an execution entity. A test case or a function is executed on a component.
Components communicate with each other or with the SUT through ports that are mapped to each other.
A test case is a sequence of sends and receives. When a message is sent to the SUT several possibles replies can be received.
Since a test case is a sequence of stimuli followed by a set of possible responses, the notation includes alternatives. It is a compact way to list all the possible alternatives in a scenario.
When sending or receiving information the value of the parameters are of paramount importance. They must be defined when sent and they must be verified when received. The template construct aims at defining the parameters values when sent or verifying the parameter values when received. Since parameters can be quite complex, defining and verifying the values is not a matter of a single line. The template allow complex verification in a single statement so that the test case stays legible.
The verdict is the result of a test case execution. It has 5 possible values: none, pass, inconc, fail, error.

Applications

TTCN-3 has been used to define conformance test suites to SIP, WiMAX, and DSRC standard protocols.
The Open Mobile Alliance adopted in 2008 a strategy of using TTCN-3 for translating some of the test cases in an enabler test specification into an executable representation.
The AUTOSAR project promoted the use of TTCN-3 within the automotive industry.
The 3GPP project promoted the use of TTCN-3 within the mobile industry.

Architecture

When executing the architecture is organized as follow:
This is an TTCN-3 example with its graphical equivalent in MSC.

module TestSystem