Packets that are sent through the ethernet are always sent to a mac address and are coming back to a mac address. The network adapter that receives these packets, compares the destination of the mac address with the mac address of the network adapter itself. If the addresses match then the packet is sent, otherwise it is repudiated.
1. MAC address works at the data link layer whereas IP address operates at the network 3 levels. It could be thought of as an IP address tales control of the software implementation whereas the MAC address supports the hardware implementation of the network stack.
2. The mac address cannot be changed as it is inserted in the device at the time of manufacturing whereas an IP address keeps on changing from one network to another
3. IP networks always maintain an association between an IP address and the Mapping address of a device. This association is referred to as ARP cache and ARP table ARP stands for address resolution protocol and keeps tabs on keeping the cache up to date.
4. Finding a mac address on a device varies from one device to another. Every device has a utility program to locate the MAC address.
5. There is a huge difference between how numbers are sequenced in an IP address that of a MAC address. IP address involves a string of u unique no. in one line whereas a MAC address has two six-digit hexadecimal numbers that are separated by a semicolon.
6. A mac address looks like this 0d:00:b1:8e:83:C1 whereas an IP address looks like 123.45.489.34.
The bit sequence of mac address is divided into 4 parts:
The first part of the mac address specifies whether it is a group or individual address. 1/G is short for individual groups. If 1/G=0 it is a unicast address for a single network adapter. Multiple cast address are identified by 1/G=1 and are addressed to several receivers
The second part of mac address specifies if the address has global validity or if the address is assigned to a local area. This is indicated by U/L. If U/L=0, then the address is assigned globally. Addresses that are locally defined are denoted by U/L=1. It is known as a universally administered address or locally administered address.
These bits encode the identifier which is associated significantly with hardware manufacturers by IEEE. This assignment is generally public.
Bits 25-48 give the manufacturing provider 24 bits to provide a unique hardware identifier
The above article summarizes everything you need to know about MAC. It covers everything from what is the full form of mac, what is mac address used for, the difference between mac and IP address, how the mack address is divided into BITS, features of a mac address, advantages of a mac address, and what are its disadvantages.