The Ethernet is both a data link (Layer 2 of OSI Model) and the physical layer(Layer 1 of OSI Model) main component for local area networks (LANs). Bob Metcalfe and D.R. Boggs invented this in 1972. Ethernet is a network protocol that controls how data transmitted over a LAN. Technically it is referred to as the IEEE 802.3 protocol. It is also used in contrast with WAN (wide area network) which spans larger geographical areas.
The Ethernet protocol standards describe many aspects of network communication as well as frame format, frame size, timing, and encoding. It’s telling, how networked devices can format data for transmission to other network devices on the same network segment, and describe how to put that data out on the network connection.
It is a contention-based method of networking. A contention-based method means that any device can try to send data across the shared medium when it has data to send. The Carrier Sense Multiple Access/Collision Detection (CSMA/CD) process uses in half-duplex Ethernet LANs to detect and resolve collisions. Today’s Ethernet LANs use full-duplex switches, which allow multiple devices to send and receive simultaneously with no collisions.
The OSI model describes separately both the data link layer function and the physical standards of the media. The Ethernet standard defines both the Layer 2 protocols and the Layer 1 technologies. According to specification, It supports different media, bandwidths, and other Layer 1 and 2 variations. The basic frame format and address scheme are the same for all types of Ethernet.