Interface Cards

Early network interface controllers were commonly implemented on expansion cards that plugged into a computer bus. The low cost and ubiquity of the Ethernet standard means that most newer computers have a network interface built into the motherboard. The NIC allows computers to communicate over a computer network, either wirelessly or by using cables or . The NIC is both a physical layer and a data link layer device, as it provides physical access to a networking medium and for IEEE 802 and similar networks, provides a low-level addressing system through the use of MAC addresses that are uniquely assigned to network interfaces.