問41
頻出度★★★
システム開発プロセスには, システム要件定義, システム方式設計, ソフトウェア方式設計, ソフトウェア詳細設計などがある。システム方式設計において実施する作業として, 適切なものはどれか。
平成22年度 秋期 ITパスポート試験 問41
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 41
Incorrectア
Designing the screens of terminals is the work of deciding in concrete terms the interface that users operate, and it is done in the software-side design processes, from software requirements definition through software architecture design and software detailed design. System architecture design is the stage of dividing the whole system into hardware, software, and manual work, and it does not go so far as the layout of each individual screen. Because this task belongs to a later process, the choice is wrong.
Incorrectイ
Defining the functions and capabilities of the system, that is, what it processes together with performance such as processing volume and response time, is the work of the preceding process, system requirements definition. That stage decides what the system must be able to do, and does not yet decide the means of realization. This choice confuses it with system architecture design, which decides the configuration that serves as the means of realization, so it is wrong.
Incorrectウ
Defining the reliability of the system, such as the availability rate and the recovery time when a failure occurs, also falls under the non-functional requirements handled in system requirements definition. After the level of reliability demanded as a requirement has been decided, system architecture design is where a concrete configuration that satisfies it, such as adopting a redundant configuration, is worked out; the definition itself is the work of the earlier process, so the choice is wrong.
- エ
正解 The correct answer is エ. System architecture design is the process that converts the “what to realize” decided in system requirements definition into “with what configuration to realize it”. Concretely, the requirements are divided into the part realized by hardware, the part realized by software, and the part realized by manual work done by people; then the hardware configuration, such as the servers and terminals that are needed, and the software configuration, such as the OS, middleware, and business software, are decided. Choice エ, “Clarify the hardware configuration and software configuration of the system”, states exactly this division and the decision of the overall configuration (architecture), so it matches the work of system architecture design. If you remember that the “architecture” in the process name means the way of realization, that is, the configuration, it becomes easier to tell this process apart from requirements definition.
ここがポイント
- The order of the processes in the Common Frame and what each one covers: system requirements definition (deciding what is to be realized, such as functions, capabilities, and reliability) → system architecture design (dividing the requirements into hardware, software, and manual work, and deciding the configuration of the system as a whole) → software requirements definition, software architecture design, and software detailed design (refining the inside of the software step by step).
- Tell them apart by a ladder of granularity: “requirements definition” is what will be built (What), “architecture design” is the configuration, that is, the way of realization (How), and “detailed design” is how the inside is actually built. For questions whose choices line up process names, you can solve them by sorting each statement along two axes: whether it describes What or How, and whether its subject is the system as a whole or the inside of the software.
用語