Cisco Certified Network Associate (CCNA) Practice Exam

Which IPv6 address type is reserved for multicast traffic?

1. Global Unicast

2. Link-Local Unicast

3. Multicast

4. Unique Local Address

The correct answer is: Multicast

The correct answer is the multicast address type, which is specifically reserved for multicast traffic in IPv6. Multicast addresses are designed to send packets to multiple destinations simultaneously without the need for creating multiple copies of the same packet. This is particularly useful in scenarios where data needs to be distributed to a group of devices, such as streaming media, video conferencing, or other applications where the same information is sent to multiple users at once. In IPv6, multicast addresses begin with the prefix FF00::/8, clearly indicating that they are dedicated to multicast purposes. This differentiates them from other address types, including global unicast and link-local unicast addresses, which are intended for one-to-one communication with specific devices or local networks. Unique local addresses are also one-to-one but are meant for use in private networks, not for multicast traffic. Understanding why multicast addresses exist and how they function helps in grasping the broader concepts of IP networking and efficient data distribution.