問90
頻出度★★★
ハードウェアなどに対して外部から不正に行われる内部データの改ざんや解読, 取出しなどがされにくくなっている性質を表すものはどれか。
令和2年度 ITパスポート試験 問90
This question's explanation and your answers so far.
解説
問 90
Incorrectア
Availability is one of the three elements of information security (CIA); it refers to the property of being able to access and use a system or information without hindrance whenever needed. It is a concept measured by metrics such as uptime rate, and does not describe resistance to tampering with or decoding a device’s internal data.
Incorrectイ
Reliability refers to the property whereby a system keeps operating correctly and stably without failing (one element of RASIS). It is a concept about operational stability, and differs from the question’s intent of resistance to unauthorized external analysis and tampering.
Incorrectウ
Accountability refers to the property of being able to later trace and identify who performed a given operation or event; it is achieved through means such as log records. It is a concept about the traceability of actions, not a property that protects a device’s internal data from physical analysis and tampering.
- エ
正解 The correct answer is エ, “Tamper resistance”. To tamper means to interfere with or alter something illegitimately. Tamper resistance is the property whereby devices such as hardware or IC cards withstand unauthorized external analysis, alteration, and reading of internal data, thereby protecting the information inside. The question’s description—internal data being made difficult to tamper with, decode, or extract by unauthorized external means—matches the definition of tamper resistance exactly. Concretely, it protects the secret information inside a device through mechanisms such as circuits that break when someone tries to open the device, or memory contents that are erased.
ここがポイント
- Tamper resistance = the property of protecting the secret information inside hardware (such as IC cards) and making it difficult for outsiders to illegitimately analyze, alter, or read that information.
- Availability, reliability, and accountability are other properties of information security or system quality, and should be memorized as distinct from tamper resistance, which denotes physical protection of internal data.
用語