They’re all valid in their own special way

Which of these is a valid IPv6 address?

A) 2001:::5a88:20a:aff

B) fe80::6ah8:30ab:30

C) fe80:1000:3a88:3011:74dc:3a90:2a77

D) 2601::5502:d101::7908

E) 2601:5:d101:700:12dd:b1ff:fe9a:1edf

F) I don’t think we need to pick favorites

The answer: E) 2601:5:d101:700:12dd:b1ff:fe9a:1edf

An IPv6 address has 128 bits, or 16 bytes represented in 8 hexadecimal groupings.
Option A is using three colons as a compression designation, which isn’t used in IPv6. Using a double colon would have made it a valid address.
Option B includes the letter h, which is not part of a valid hexadecimal address. Hex values are from 0 through 9 and a through f.
Option C is only 14 bytes long.
Option D uses the double colon twice, which is not a valid compression technique.

Want to know more? Watch “An Overview of IPv4 and IPv6.”

The primary IP technologies used today are IP version 4 and IP version 6. In this video, you’ll learn the differences between these two technologies, the differences between public and private IP addressing, and how automatic private IP addressing (APIPA) can be used to provide connectivity.