The Media Access Control Layer is one of two sublayers that make up the Data Link Layer of the OSI model. The MAC layer is responsible for moving data packets to and from one Network Interface Card (NIC) to another across a shared channel.

The MAC sublayer uses MAC protocols to ensure that signals sent from different stations across the same channel don't collide. Different protocols are used for different shared networks, such as Ethernets, Token Rings, Token Buses, and WANs.