問100
頻出度★★★
個人の認証に用いる要素を，知識，所有物及びバイオメトリクスの三つに分類したとき，所有物を要素として用いた認証の例はどれか。
令和7年度 ITパスポート試験 問100
This question's explanation and your answers so far.
解説
問 100
- ア
正解 The three factors of authentication are classified as: knowledge (information only the person knows, such as a password), possession (something only the person has), and biometrics (physical or behavioral characteristics unique to the person, such as fingerprints or iris patterns). Choice “ア”, authentication using SMS, sends a one-time code to the number of the smartphone (mobile phone) the person owns, and the person enters that code—this confirms that they possess the device, making it a correct example of authentication that uses “possession”.
Incorrectイ
Authentication using iris features relies on the iris of the eye, a physical characteristic unique to the person, so it is classified as biometrics, not possession.
Incorrectウ
Authentication using characteristics of writing such as handwriting, pen pressure, and speed relies on behavioral characteristics unique to the person, so it is behavioral biometrics, not possession.
Incorrectエ
Authentication using a question set in advance by the person and its answer is based on information only the person knows (a secret question), so it is knowledge-based authentication, not possession.
ここがポイント
- Understand how to distinguish the three authentication factors: knowledge (what you know: passwords, secret questions) / possession (what you have: smartphones, IC cards, tokens) / biometrics (the person's own characteristics: fingerprints, iris, handwriting, etc.).
- Remember this typical example: SMS authentication is classified as “possession” because the code is sent to the smartphone the person owns.
用語