Cisco Certified Network Associate (CCNA) Practice Exam 2026 – The Comprehensive All-in-One Guide to Exam Success!

When a node has not learned its own IPv6 address, it is assigned a source address of 0:0:0:0:0:0:0:0, which is the unspecified address in IPv6. This address represents "no specific address" and is used when a device does not yet have an address assigned to it.

In this scenario, the device may use this unspecified address when initiating communications or trying to acquire an address through mechanisms such as DHCPv6. It indicates that the source does not yet possess a valid IPv6 address.

The other addresses presented serve different purposes. The address 0:0:0:0:0:0:0:1 is the loopback address and is used by a device to send packets to itself, not for communicating with other nodes. The FE80::/10 range represents link-local addresses that are used for communication within a single network segment, but a node must have a valid address to use them. The 2001:0db8::/32 address is designated for documentation purposes and is not used for actual network communication. Thus, when a device has no learned IPv6 address, it correctly defaults to the unspecified address of 0:0:0: