Notations for Test Specification: TTCN3 and ASN.1

Testing and Protocol Testing

Testing is part of our everyday lives. This can be demonstrated with the help of a simple example - the common scenario of picking up a cup of tea from the table and drinking it. The action is so natural that we do not think about the parallel flows needed for it. Let us have a look at this situation from testing point of view. The human brain provides many parallel functions in the area of test and control. Two senses are used to pick up the cup: vision and touch. The hand is under control during the whole period. The brain controls the position of the hand and the strength of the grasp. If any control function of the brain is missing, medical science identifies it as an illness.

The example above helps us to understand the definition of testing: to test is to verify a process. This is a rather general description of testing. More exact definitions can also be found in this chapter. We can observe the following: The more information that exists about a function, we get more correct definition of “a process”. Below are some questions worth considering:

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  Where is testing needed?

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  Why is testing needed?

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  Who/What needs testing?

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  Is testing always necessary?

The answer to the first question comes from the above stated definition of testing. In short, it means that tests have to be used in everywhere where something should be controlled. The main answer to the second question is to minimize the errors of a given system. The answer to the third question depends on who/what wants to control certain processes. The final response is clear: test flows can never be ignored.

Testing is a special process, because every test is unique. That is why a universal test process cannot be created. Difficulties arise from the complexity of the system being tested, the environment in which the test was performed, and the evaluation of the results – since we can test the simple process of picking up a cup, as well as a complex economical process. Basically, we have to know three things for building a test:

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  Test goal

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  Access point(s)

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  Reliable method(s)

The test goal states exactly what needs to be controlled or checked. The tester can enter the system under test at the access point, and the test can be executed with the help of a reliable method.