問37
頻出度★★★
ソフトウェア要件として明確に規定すべきものはどれか。
平成21年度 秋期 ITパスポート試験 問37
マネジメント系システム開発技術 › システム開発技術
This question's explanation and your answers so far.
解説
問 37
Incorrectア
The disk capacity of the development environment is an environmental condition needed by the development side to do its work, not a requirement that the finished software must satisfy. Preparing the development environment is handled in development planning and project management.
Incorrectイ
The objectives of the system development are higher-level aims decided in the planning process, that is, in the system concept and system plan, and they are fixed at a stage before software requirements definition. Requirements are made concrete on the basis of those objectives, so the objectives themselves are not what is specified as a software requirement.
- ウ
正解 The correct answer is ウ, data definitions. In software requirements definition, the input and output data handled by the software, together with the name, meaning, type, number of digits, and range of possible values of each data item, must be fixed without ambiguity. If the data definitions are not settled, differences in interpretation arise in the later design, implementation, and testing work, and this causes rework. Data definitions are therefore part of the functional requirements and must be clearly specified as software requirements.
Incorrectエ
The top-level design of the database is a deliverable of the design process, which decides how something is realized. Requirements definition specifies only what is needed. Fixing design content that already commits to a realization method as a requirement would unduly remove freedom from the design work.
ここがポイント
- Software requirements definition specifies what is to be realized (What), while how it is realized (How) is decided in the later design process. Data definitions belong to the What side and form the core of the functional requirements.
- Keep in mind the order of the processes, planning (objectives of the system development), then requirements definition (functional and non-functional requirements), then design (database design and so on), and the distinction between the deliverables of each process.
用語