What is the multicast Ethernet address for IP address 227.128.64.12?
The base Ethernet multicast address is 01 00 5E 00 00 00. The first byte of the IP multicast address is not used. If the second byte is greater than 127, subtract 128, giving a value of 0. The third and fourth bytes of the IP address are used as-is after converting to hex. Their values, in hexadecimal, are 40 and 0C. So the Ethernet multicast address for the IP multicast address 227.128.64.12 is 01 00 5E 00 40 0C.
