Ethernet Addressing (MAC)
Last updated
Last updated
Address is also called MAC Address (Media Access Control).
MAC Address is 6 Bytes, 48 bits Hexadecimal Address.
This MAC Address is made up of 6 Sets & each Set includes 8 bits of Hexadecimal characters separated by periods.
MAC Address is pre-programmed in every NIC card.
IEEE Assigns the first 3 Bytes unique to the NIC card called the Organizationally Unique Identifier (OUI). And the manufacturer assigns the remaining 3 Bytes unique to every NIC card that they manufacture.
In this way, No two NIC cards will have the same MAC Address. Hence MAC Address is also called a Unicast Ethernet Address, LAN address, Ethernet address, hardware address, burned-in address, physical address & universal address.
6 Bytes (48 Bits) MAC Address:
OUI
Vendor
24bits
24bits
00 60 2F
3A 07 BC
(6 Hex digits)
(6 Hex digits)
Apart from the Unicast Ethernet Address, Ethernet also uses Group Addresses which are divided into two categories:
Broadcast Address:
Frame sent to this address will be delivered to all the devices of that LAN. It is FF:FF:FF:FF:FF:FF
Multicast Address:
Frame sent to this address will be copied & delivered to a group belonging to that specific Multicast address & not to all the devices.
Reference:
CCNA 200-301 OCG, Volume 1, Pg. 50-51 - Wendell Odom.