What is Ethernet?
Overview
Ethernet is the dominant cabling and low level data delivery technology used in local area networks (LANs).
- Ethernet transmits data at up to ten million bits per second (10Mbps). Fast Ethernet supports up to 100Mbps and Gigabit Ethernet supports up to 1000Mbps.
- Ethernet supports networks built with twisted-pair (10BaseT), thin and thick coaxial (10Base2 and 10Base5, respectively), and fiber-optic (10BaseF) cabling. Fast Ethernets can be built with twisted-pair (100BaseT) and fiber-optic (100BaseF) cabling. Currently, 10BaseT Ethernets are the most common.
- Data is transmitted over the network in discrete packets (frames) which are between 64 and 1518 bytes in length (46 to 1500 bytes of data, plus a mandatory 18 bytes of header and CRC information).
- Each device on an Ethernet network operates independently and equally, precluding the need for a central controlling device.
- Ethernet supports a wide array of data types, including TCP/IP,
AppleTalk, and IPX.
- To prevent the loss of data, when two or more devices attempt to send packets at the same time, Ethernet detects collisions. All devices immediately stop transmitting and wait a randomly determined period of time before they attempt to transmit again.