問55
頻出度★★☆
情報システムの要件は, 業務要件を実現するための機能を記述した機能要件と, 性能や保守のしやすさなどについて記述した非機能要件に分類することができる。 機能要件に該当するものはどれか。
平成28年度 春期 ITパスポート試験 問55
ストラテジ系システム企画 › 要件定義
This question's explanation and your answers so far.
解説
問 55
- ア
正解 The correct answer is ア. A functional requirement defines what the system specifically does in order to fulfill the business requirements (what data it handles and how it processes them). Choice ア, “the types of input/output data handled by the system,” refers to the very data that the system receives as input and returns as output — that is, it specifies the substance of the business functions the system must perform, so it qualifies as a functional requirement.
Incorrectイ
“The allowable recovery time when a system failure occurs” indicates the level of availability and reliability — how quickly the system can recover from a failure. This is a non-functional requirement concerning performance and ease of maintenance. It defines not what the system does but at what quality level it operates, so it is not a functional requirement.
Incorrectウ
“The migration procedure for the system” is an arrangement on the migration and operational side — how to switch over from the old system to the new one. It is classified as a non-functional requirement (migration requirement). Because it does not describe a business function itself, it is not a functional requirement.
Incorrectエ
“The target system quality and development cost” is a constraint or goal — the quality level and cost to be achieved — not a function itself. Quality is a non-functional requirement and cost is a project constraint; neither is a functional requirement.
ここがポイント
- Functional requirement = a description of what the system does (input/output data, processing, business functions) in order to fulfill the business requirements.
- Non-functional requirement = a description of at what level the system operates, covering performance, reliability (availability, recovery time), maintainability, migration, quality, and so on.
用語