What is the connection between Medium Access Control(MAC) and the hardware MAC address?

Question

For example in an ethernet where all hosts share a common broadcast link for each host to have access to the link there is Medium Access Control like the CSMA/CD protocol.

Also any communications hardware device(Computer NIC, bluetooth adaptor, mobile phone, etc) has a "MAC address". How is this 'MAC address' related to the above mentioned Access Control?

Answer 1

Medium Access Control is a protocol that operates on the data link layer in the OSI model.



MAC address or burnt in address or hardware address is a physical address and each network adapter has one. They're made up of 6 octets.



The first 3 identify the company that made it and the last 3 are the card's unique number so as long as the company doesn't make 2 cards with the same unique card number, no 2 cards will have the same MAC address. Unlike IP addresses that you can easily change, MAC addresses can't be changed (easily).



MAC addresses are used by IP. Switches, routers and other devices use MAC addresses for local routing on LANs. ARP (Address Resolution Protocol) is used to map MAC addresses to IP addresses.



TCP/IP uses Ethernet to communicate with other computers but it can also be used (or at least certain protocols of it) are used in what's known as Interprocess Communication (IPC) where processes on a computer can "talk" to each other.



Now we get into threads and talking to the kernel and stuff like that etc. but that's a whole different story.



Hope I've confused you enough :)



Cheers

Answer 2

MAC address is just the address for Media Access Control layer, and it is Media, not Medium. Equate this to an IP address being an address for the Internet Protocol layer. It just defines a device at the layer.

Answer 3

well there is a MAC and you are thinking of the same thing.



Mac operates on hardware and software level. It operates on a sub layer of layer 2.