Are IPv4 multicast addresses in the range 224.0.0.0 to 239.255.255.255, and what is their purpose?

• A. Yes; used for one-to-many delivery to a group of hosts.
• B. No; multicast range is different.
• C. Yes; used for one-to-one delivery.
• D. Yes; only for experimental multicast traffic.

Answer: (A)

Multicast addresses in IPv4 are designed for one-to-many delivery. The address range 224.0.0.0 through 239.255.255.255 is reserved for IPv4 multicast, meaning a single sender can transmit a packet that is delivered to all hosts that have joined the multicast group. This lets you stream data, such as video or real-time updates, to many receivers efficiently without sending separate copies to each one. Hosts join or leave multicast groups using IGMP, and routers use multicast routing protocols (like PIM or DVMRP) to forward traffic only toward interested receivers. Within this range there are some special cases, such as 224.0.0.1 for all hosts on the local network, but the overarching purpose remains one-to-many delivery to a group.