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LFCS · Question #57

Which of the following is a valid IPv6 address?

The correct answer is A. 2001:db8:3241::1. This question tests the understanding of IPv6 address syntax rules, including the use of hexadecimal digits and the single double-colon abbreviation.

Submitted by omar99· Apr 18, 2026Networking

Question

Which of the following is a valid IPv6 address?

Options

  • A2001:db8:3241::1
  • B2001::db8:4581::1
  • C2001:db8:0g41::1
  • D2001%db8%9990%%1
  • E2001.db8.819f..1

How the community answered

(50 responses)
  • A
    92% (46)
  • B
    2% (1)
  • C
    4% (2)
  • D
    2% (1)

Why each option

This question tests the understanding of IPv6 address syntax rules, including the use of hexadecimal digits and the single double-colon abbreviation.

A2001:db8:3241::1Correct

This is a valid IPv6 address; it uses correct hexadecimal digits and employs a single double-colon (::) to represent a block of zero segments, which is a permissible abbreviation.

B2001::db8:4581::1

An IPv6 address can contain only one double-colon (::) abbreviation, but this address has two, making it invalid.

C2001:db8:0g41::1

The segment `0g41` is invalid because 'g' is not a valid hexadecimal digit (which must be 0-9 and a-f).

D2001%db8%9990%%1

IPv6 addresses use colons (:) as segment separators, not percentage signs (%), making this format incorrect.

E2001.db8.819f..1

IPv6 addresses use colons (:) as separators, not dots (.), and the `..` notation for abbreviation is incorrect; only `::` is valid.

Concept tested: IPv6 address syntax rules

Source: https://learn.microsoft.com/en-us/windows-server/networking/technologies/ipv6/ipv6-overview#ipv6-addressing

Topics

#IPv6#IP Addressing#Network Syntax

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