Which of the following are NOT valid IPv6 addresses? (Choose all that apply.)

A.
225.1.4.2

B.
::FFFF:10.2.4.1

C.
::

D.
2001:0:42:3:ff::1

E.
fe80:2030:31:24

F.
2001:42:4:0:0:1:34:0

G.
2003:dead:bef:4dad:ab33:46:abab:62

Explanation:
The addresses 255.1.4.2 and fe80:2030:31:24 are not valid IPv6 addresses.
225.1.4.2 is incorrect because it is an IPv4 multicast address. The address fe80:2030:31:24 is incorrect
because it does not represent a 16-byte IPv6 address, with colons separating each 2-byte segment.
IPv6 addresses are 16 bytes, or 128 bits in length. The following are valid IPv6 addresses.
::FFFF:10.2.4.1 is an example of an IPv4-compatible IPv6 address, where the first 10 bytes (80 bits) of the
address are set to 0 the next 2 bytes (16 bits) are set to FFFF and the last 32 bits are the IPv4 address
:: is the IPv6 “unspecified address.” It is a unicast address not assigned to any interface, and is used by a
DHCP-dependent host prior to allocating a real IPv6 address.
2001:0:42:3:ff::1 is a valid IP address, with the :: representing two segments (4 bytes) of compressed zeros.
2001:42:4:0:0:1:34:0 is a valid IP address, with only the leading zeros of each segment truncated.
2003:dead:beef:4dad:ab33:46:abab:62 has 16 bytes, is divided correctly by colons into eight sections,
utilizes the dropping of leading zeros in each section correctly, and uses the letters a-f in the three section
that spell out dead beef 4 dad.
Objective:
Network Fundamentals
Sub-Objective:
Compare and contrast IPv6 address types

Cisco > Technology Support > IP > IPv6 > Technology Information > Technology White Paper > IPv6
Addressing At A Glance (PDF)
Cisco > Internetworking Technology Handbook > IPv6