Cisco Exam Questions

Select the valid IPv6 addresses. (Choose all apply)

Select the valid IPv6 addresses. (Choose all apply)

A.
::192:168:0:1

B.
2002:c0a8:101::42

C.
2003:dead:beef:4dad:23:46:bb:101

D.
::

E.
2000::

F.
2001:3452:4952:2837::

Explanation:
Answers A B C are correct because A and B are the short form of 0:0:0:0:192:168:0:1 and 2002:c0a8:0101:0:0:0:0:0042 while C are normal IPv6 address.

Answer D is correct because :: is named the unspecified address and is typically used in the source field of a datagram that is sent by a device that seeks to have its IP address configured.

Answer E is not correct because a global-unicast IPv6 address is started with binary 001, denoted as 2000::/3 in IPv6 and it also known as an aggregatable global unicast address.The 2000:: (in particular, 2000::/3) is just a prefix and is not a valid IPv6 address.

The entire global-unicast IPv6 address range is from 2000::/128 to 3FFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF/128, resulting in a total usable space of over 42,535,295,865,117,307,932,921,825,928,971,000,000 addresses, which is only 1/8th of the entire IPv6 address space!