問51
頻出度★★★
メールサービスにおける IT サービスマネジメントの可用性の要件に関する事例として, 適切なものはどれか。
平成30年度 秋期 ITパスポート試験 問51
マネジメント系サービスマネジメント › サービスマネジメントシステム
This question's explanation and your answers so far.
解説
問 51
Incorrectア
Making the service usable with just a web browser concerns the means of use and ease of access (usability, portability), which differs from the availability requirement of whether the service can be used when one wants to use it.
- イ
正解 Availability is a quality characteristic expressing the degree to which a system or service can be used when users want to use it; in IT service management it is managed through operating rate and downtime. Choice イ, “Make the email service usable at any time except during the prescribed maintenance window,” requires keeping the service continuously available apart from planned outages (maintenance), which is exactly an example that states an availability requirement. Therefore イ is correct.
Incorrectウ
Preventing others from reading email addressed to oneself without permission is a requirement of confidentiality, which keeps information from being shown to anyone other than authorized parties, and is not availability.
Incorrectエ
Ensuring that sent email cannot be tampered with is a requirement of integrity, which keeps information accurate and unaltered, and is not availability.
ここがポイント
- Availability = the degree to which users can use something when they want to. Keeping it continuously available except during planned maintenance windows is a typical availability requirement.
- Do not confuse this with the three elements of information security. Distinguish them clearly: confidentiality = not letting others read, integrity = no tampering, availability = usable at any time.
用語