A baseband local-area network (LAN) originally developed by Xerox and supported by Intel, Digital Equipment (now Compaq Computer) and Hewlett-Packard. It has a bus topology with carrier sense multiple access with collision detection (CSMA/CD) access control. Ethernet is not identical to Institute of Electrical and Electronics Engineers (IEEE) 802.3. Related terms include:

• Ethernet address: 48-bit code for Layer 2 networking maintained by the IEEE and hardwired into network adapters; also called MAC address.
• Ethernet, thick: Ethernet coaxial cable suitable for networks that are medium/large or with widely spaced nodes.
• Ethernet, thin: Ethernet coaxial cable suitable only for small networks with closely connected nodes.