In 1979, DEC, Intel, and Xerox Corporations standardized on an Ethernet version that any company could use anywhere in the world. In September 1980, they released Version 1.0 of the DIX standard, so named because of the initials of the three founding companies. It defined the so-called thick Ethernet or Thicknet version of Ethernet (10Base5), which offered a 10 Mbps CSMA/CD protocol. It was called Thicknet because it relied on relatively thick coaxial cable for interconnections among the various devices on the shared network. The first DIX-based controller boards became available in 1982, and the second (and last) version of DIX was released in late 1982.

In 1983, the IEEE released the first Ethernet standard. Created by the organization s 802.3 ^[1] Committee, IEEE 802.3 Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method and Physical Layer Specifications was basically a reworking of the original DIX standard with changes made in a number of areas, most notably to the frame format. However, because of the plethora of legacy equipment based on the original DIX specification, 802.3 permitted the two standards to interoperate across the same Ethernet LAN.

The ongoing development and tightening of the standard continued over the next few years. In 1985, IEEE released 802.3a, which defined thin Ethernet, sometimes called cheapernet (officially 10Base2). It relied on a thinner, less expensive coaxial cable for the shared medium that made installation significantly less complex. Although both media offered satisfactory network performance, they...