令和3年度 ITパスポート試験問98

This question's explanation and your answers so far.

問98

頻出度★★★

インターネットで用いるドメイン名に関する記述のうち, 適切なものはどれか。

出典　令和3年度 ITパスポート試験問98

解説

問 98

Incorrectア
It is true that letters, digits, and hyphens can be used, but the claim that “kanji and hiragana cannot be used” is incorrect. Thanks to the internationalized domain name (IDN) mechanism, domain names containing Japanese (kanji and hiragana) can also be obtained and used. Therefore this option is inappropriate.
Incorrectイ
A domain name is not used only in Web URLs. The part after the “＠” in an email address (for example, the example.co.jp in “user＠example.co.jp”) is also a domain name and is used in email addresses too. Therefore this option is incorrect.
Incorrectウ
Domain names are not limited to companies or organizations; individuals can obtain them too. There are many domains that individuals can register, such as general-use JP domains and various gTLDs, so this statement is incorrect.
エ
正解 A domain name is a representation in which an IP address (a string of numbers) is replaced with a character string that is easy for people to identify and remember (for example, “example.co.jp”). In actual communication, DNS converts this domain name into the corresponding IP address (name resolution). Therefore, option エ, which states that a domain name represents a connection destination as a character string that is easy for people to identify and is used in place of an IP address, correctly describes the role of a domain name and is appropriate.

ここがポイント

A domain name represents a connection destination with a character string that is easy for people to identify, in place of a hard-to-remember IP address, and DNS maps the two to each other (name resolution).
Domain names are used not only in URLs but also in email addresses; individuals can also obtain them, and Japanese can be used thanks to IDN.

用語

解答問98エ