The detailed demand is the basis of the system test. In turn, it can only be used to determine whether the software meets the needs. You must test the entire software for the expected behavior of the product recorded in the software requirements specification, not for design or encoding. Code-based system testing can become "self-fulfilling prophecy". The product can correctly present all the behaviors described based on code-based test cases, but this does not mean that the product correctly implements users' needs. If you don't have a demand for document form, you should re-access your needs to develop appropriate test cases, which will be a inefficient and inaccurate approach. Let the test personnel participate in the demand review to ensure that the demand is clear, and through the verification needs can be used as the basis for system testing. During the development of development, you will carefully scrutinize the demand of high-level abstraction using instances, and eventually convert to a single code module specification. The authoritative expert BORIS BORIS BORIS BORIS BORIS BORIS BORIS BORISER (1999) indicates that the testing of the demand must be carried out at each layer of the software structure, not just in the user layer. There are many codes in an application that will not be accessed by the user, but these codes are required for product infrastructure. Even if some module functions are not visible to the user throughout the software product, each module function must meet its own needs or specifications requirements. Therefore, it is necessary to test the system to test the system test but non-sufficient conditions.
