A way to allow computers to transmit signals over network cabling, while ensuring that only one computer transmits at a time. If two computers simultaneously place signals on the wire, a collision can occur and data might be corrupted unless a method is used to resolve the collision gracefully. Media access control methods act like traffic lights by permitting the smooth flow of traffic on a network, and they prevent or deal with collisions. Media access control methods are implemented at the data-link layer of the Open Systems Interconnection (OSI) reference model.
Four main media access control methods are used in networking: