IPA IP 2022 Question 73
A question IPA Japan published in 令和4年度 ITパスポート試験 公開問題 問73, translated into English. ITPEC is based on the same exams.
Same question on ITPEC: Apr 2024 Q34
A large number of IP addresses are required in order to connect a massive number of IoT devices to the Internet, so the decision was made to use the Internet Protocol with IP addresses that have a length of 128 bits. Which of the following is this protocol?
Explanation
IPv6 — the version of the Internet Protocol with 128-bit addresses, created because 32-bit IPv4 addresses were running out.
IPv4 addresses are 32 bits long, which allows about 232, some 4.3 billion, addresses: not enough once PCs, smartphones and a massive number of IoT devices all need one. IPv6 lengthens the address to 128 bits, about 2128 addresses, so practically every device can have its own global address. IPv6 addresses are written as eight groups of four hexadecimal digits separated by colons.
Answer (c)
Why not others:
- •(a) IPv4 — the widely used version whose addresses are 32 bits long; its shortage is the problem the question describes
- •(b) IPv5 — the version number was taken by an experimental streaming protocol that was never deployed as an Internet Protocol for addressing
- •(d) IPv8 — no such standard Internet Protocol exists
Key rule: IPv4 addresses are 32 bits in dotted decimal, IPv6 addresses 128 bits in colon-separated hexadecimal; the move to IPv6 answers the shortage of IPv4 addresses.
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.