Ethernet

The Ethernet technology was born in 1973 and developed by a researcher Bob Metcalfe at Palo Alto Research Center in Xerox Corporation. The purpose of the Ethernet is to connect network devices physically by cables, so devices on the network will able to communicate with each other.

When a device or a station sends data through the network, the data frame will contain a destination address, so only the computer with the corresponding address on the Ethernet will open the data. The Ethernet also use a technique called broadcast, all the stations on the Ethernet can use broadcast address to send data and this piece of data can be receive and open by all the stations on the Ethernet. 

Ethernet are connecting by physical cables, if the length of the cable is too long, the Ethernet will start losing signals when transmit data from one end to another end due to the fact that signals are getting weak when they travel along cables. The device called repeater is made for reduce the lost signals. It regenerate the signals as it get from on end of the network and send to another end of the network, therefore the Ethernet can be extend longer by using repeaters.

Ethernet use a protocol called CSMA/CD to rule the network. CSMA/CD protocol has indicate that only one device can transmit data on the network at same time and other computers will have to listen to the network work before they send data. Although Ethernet technology use a protocol called CSMA/CD technology to reduce the data collisions on the network, but the collisions may still occur on the network and if that happens both of computer or device who made the collision will stop sending data for a period of time and after the line is clean they will try to send their data again. In an advance way to reduce the network collision is to install bridge, switch or subnet the network. A bridge will stop the data transmission from one side of the network to another side of network across the bridge, if the data is not useful for the other end of the network. A switch is more advance that the bridge it will only transmit data from one computer to the computer who needs it, so there may be more than one computer can transmit and receive data at the same time with no collision.

Ethernet is very popular today as many companies are using it to connect their network. Ethernet is also get improving with other new technologies, such as the cables use to connect the Ethernet can be change to faster mediums and other device on the Ethernet will also get improved to have more functions and more reliable..