問59
頻出度★★★
コンピュータなどのアカウントに設定するパスワードに関し, 使用する文字種や長さなどの条件を定めたものはどれか。
平成29年度 秋期 ITパスポート試験 問59
This question's explanation and your answers so far.
解説
問 59
Incorrectア
Single sign-on (SSO) is a mechanism that lets a user, after authenticating just once, go on to use multiple systems or services. It reduces the burden of authentication for the user; it does not define conditions such as the character types or length of passwords.
Incorrectイ
Password cracking is an attack or technique that illegitimately works out someone else’s password by means such as brute force (exhaustive trials) or dictionary attacks. It is on the side that breaks passwords, not the side that defines conditions, which is the exact opposite of what the question asks.
- ウ
正解 The correct answer is “ウ Password policy.” A password policy is a set of rules that an organization or system defines in advance for the passwords set on accounts — such as which character types may be used (uppercase letters, lowercase letters, digits, symbols, etc.), the minimum number of characters (length), the expiration period, and a ban on reusing previously used passwords. This matches exactly the wording in the question, “defines conditions such as the types of characters and the length used.” It is used to prevent weak passwords and to improve safety against guessing and cracking.
Incorrectエ
A one-time password is a disposable password that is valid only for a limited time or only once; it is an authentication method that prevents unauthorized logins caused by eavesdropping or reuse. It is an individual means of authentication, not something that defines conditions (rules) such as character types or length.
ここがポイント
- Password policy = a set of rules an organization defines in advance, covering a password’s character types, minimum number of characters (length), expiration period, ban on reuse, and so on; it is used to prevent weak passwords and improve safety.
- Distinguishing confusing terms: single sign-on (authenticate once to use multiple systems), password cracking (an attack that breaks passwords), and one-time password (a disposable authentication method) — none of these is a rule that defines conditions.
用語