Ethernet is the most common LAN (Local Area Network) technology in use today. Ethernet was developed by Xerox in the 1970s, and became popular after Digital Equipment Corporation and Intel joined Xerox in developing the Ethernet standard in 1980. Ethernet was officially accepted as IEEE standard 802.3 in 1985.The original Xerox Ethernet operated at 3Mbps. Ethernet networks up to 10Gbps now exist.
The first Ethernet standard, 10Base-5, ran over thick coaxial cable. A later standard, Ethernet 10Base-2, ran over a much thinner coaxial cable. These two versions of Ethernet were colloquially known as thicknet and thinnet.
Modern Ethernet standards run on UTP (Unshielded Twisted Pair) or fiber-optic cabling.
|Ethernet Standard||Cable Specification|
|10Base-T||Category 3 UTP|
|100Base-TX||Category 5 UTP|
|1000Base-T||Cat 5e UTP|
Ethernet 10Base-5 and 10Base-2 used a bus topology. Bus topologies were difficult to maintain and troubleshoot.
Modern Ethernet networks use a star topology with an Ethernet hub, switch, or router at the center of the star.
It is still possible to create a two-node Ethernet network in a bus topology using a null-Ethernet cable between the two devices. Read the rest of this entry »