問86
頻出度★★★
二要素認証の説明として, 最も適切なものはどれか。
令和2年度 ITパスポート試験 問86
This question's explanation and your answers so far.
解説
問 86
- ア
正解 The three factors of authentication are three categories: “something you have (a possession: an IC card, a token, etc.)”, “something you know (knowledge: a password, a PIN, etc.)”, and “biometric information (the person’s own traits: a fingerprint, an iris, etc.)”. Two-factor authentication refers to a method that combines two different categories among these to verify a person’s identity. Choice ア states that it “authenticates using two of the three categories”, which correctly matches this definition, so it is the correct answer.
Incorrectイ
This describes a method that uses biological organs or handwriting and compares two or more feature points of the authentication information, which is merely about the internal processing of biometric authentication. It uses only one category of factor, namely “biometric information”, so it does not become two-factor, making it incorrect.
Incorrectウ
This describes a complex password combining two or more of letters, numbers, and symbols. Although it is a technique for making a password stronger, it uses only one category of factor, namely “something you know”. Because there is only one category of factor, it is not two-factor authentication, so it is incorrect.
Incorrectエ
A method that lets a user use multiple systems or services after being authenticated only once is a description of Single Sign-On (SSO), which is about a mechanism for skipping repeated authentication. It has nothing to do with the number of factors used, so it is incorrect.
ここがポイント
- The three factors of authentication = something you have (a possession), something you know (knowledge), and biometric information (the person’s own traits). Combining two different categories is two-factor authentication; combining two or more categories is multi-factor authentication.
- Even stacking two of the same factor (for example, two passwords) does not make it two-factor authentication. The key point is that you must combine factors of different categories.
用語