Editing Multicast (section)

==Ethernet==
[[Ethernet frame]]s with a value of 1 in the least-significant bit of the first octet of the [[MAC address|destination address]] are treated as multicast frames and are flooded to all points on the network. This mechanism constitutes multicast at the data link layer. This mechanism is used by IP multicast to achieve one-to-many transmission for IP on Ethernet networks. Modern Ethernet controllers filter received packets to reduce CPU load, by looking up the hash of a multicast destination address in a table, initialized by software, which controls whether a multicast packet is dropped or fully received.

Ethernet multicast is available on all Ethernet networks. Multicasts span the [[broadcast domain]] of the network. [[Multiple Registration Protocol]] can be used to control Ethernet multicast delivery.