Ethernet
alias ： 802.3, IEEE 802.3
Ethernet is a LAN standard devised by Xerox and DEC (one department of Hewlett Packard now). Ethernet was standardized by the committee IEEE 802.3. CSMA/CD is applied to the access control.
Lately, most LANs are becoming Ethernet, except for special purpose.
There are two types of topologies for Ethernet; Bus topology, in which several devices share one line and star topology, in which each device is connected through hub. Moreover, topologies can be categorized more based on the highest transmission distance or baud rate.
10BASE-2 is a bus topology using Thin coax as a cable whose baud rate is 10Mbps, highest transmission distance is 185m and maximum number of devices connected is 30.10-BASE-5 is a bus topology using Thick coax whose baud rate is 10Mbps, highest transmission distance is 500m, and maximum number of devices connected is 100. The most widely used star topology is 10BASE-T using UTP, whose baud rate is 10Mbps, highest transmission distance is 100m. Cascading connection of hub is up to 3.
Fast Ethernet, whose baud rate is 100Mbps, for example, 100BASE-TX, is spreading. Gigabit Ethernet, which enables 1Gbps of baud , is also becoming popular, represented by 1000BASE-T, one which has high compatibility of physical layer with 100BASE-TX.
"Ethernet" was originally the name for 10Mbps type of LAN standard, but now the word is being used as a general term for both Fast Ethernet and Gigabit Ethernet.