Question: what is a valid multicast mac address?
Answer: Multicast IP addresses, which range from 224.0. 0.0 to 239.255. 255.255, are defined by the leading address bits of 1110. ... To support IP multicasting, the Internet authorities have reserved the multicast MAC address range of 01:00:5E:00:00:00 to 01:00:5E:7F:FF:FF.