IPA IP 2024 Question 71
A question IPA Japan published in 令和6年度 ITパスポート試験 公開問題 問71, translated into English. ITPEC is based on the same exams.
Which of the following is an appropriate description of a domain name that is used on the Internet?
Explanation
A name for identifying computers, networks, etc. — a domain name is the readable name of a network or a computer on the Internet, in place of its IP address.
A domain name such as itpec. names an organization’s network, and a host name in front of it, as in www., names one computer in it. Computers communicate by IP addresses, so DNS translates the name into the IP address before communication starts. Domain names are hierarchical, read from the right: the top-level domain (org, jp), then the names registered under it.
Answer (b)
Why not others:
- •(a) — the rules that web browsers and mail software follow are protocols such as HTTP, SMTP and POP3, not domain names
- •(c) — the application that a communication is for is identified by a port number (80 for HTTP, 25 for SMTP)
- •(d) — the destination of an e-mail is an e-mail address; only the part after “@” is a domain name, and it names the receiving organization’s mail domain, not the person
Key rule: An IP address and a domain name both identify a computer or network (DNS maps one to the other), a port number identifies the application, and a protocol is the set of rules they communicate by.
Networks · AI-written, may contain errors
This question comes from the past questions IPA Japan publishes, translated into English by ITPEC Practice. ITPEC Practice is an independent study tool and is not affiliated with IPA or ITPEC. See the original paper (PDF) or Report an issue.