Special MAC addresses

[Danimal1209]

So, I have a problem on one of my assignments. The teacher is asking this question:

(6 points) Define the type of the following destination Ethernet MAC address. Explain your answer:
1) 67:40:00:91:88:1A
2) FF:FF:FF:FF:FF:FF
3) 1C:4D:1D:3D:3F:00

I know that #2 is a broadcast address, but I cannot find any information on the other two. I am assuming one is a multicast address, but I don't know which one.

I've read the pages he's assigned and they contain no information that would help.

Any help? It's not a big deal for points, but I want to know what they are used for. Thanks.

Edit: The smiley faces are D's

 

[mcmilljb]

Do you know what the other types are?

After you know that, what defines those types of addresses?

 

[spidey07]

THere is a special range for multicast MAC addresses, they map directly to the multicast IP address (224. - 239.). Take a look at the first byte in the MAC and it will be clear which one is a mcast. Broadcast and multicast are the only "special" mac addresses, all others would be unicast. Unless you're talking about gateway redundancy protocols like HSRP or VRRP.

 

[Danimal1209]

Thanks guys!