ETHERNET, FAST ETHERNET AND GIGABIT ETHERNET

Ethernet

• Ethernet is a base band networking technology that has been defined by various standards. A base band technology devotes the entire bandwidth of the media to one channel. Simplistically, bandwidth can be defined as a measure of network capacity - the greater the available bandwidth, the greater the network's resilience to loading. The inclusion of the word "base" in 10BaseT, 10Base5 etc., simply refers to Ethernet’s base band nature.

• There are no levels of priority for transmission. All computers on an Ethernet network are considered equal in terms of their access to the media. In contrast to token ring, there is no monitoring station that controls the network.

• Ethernet uses carrier sensed multiple access with collision detection (CSMA/CD) as its method of medium access control.

• data in the ether is accessible to all connected devices.

• high loading on a LAN segment can lead to packet collisions and a marked drop in network efficiency.

• Ethernet has a broadcast logical topology - data is sent to all nodes on the network  simultaneously

• As shown in the diagram, Ethernet is the most dominant LAN technology :-

 

• The figures represented in the pie chart are relatively out of date, although Ethernet still remains the most common LAN architecture. ATM has become important as a LAN technology in areas of the computing industry where high data transfer rates are required. Multimedia, computer graphics and video conferencing all need fast networks, therefore ATM is a good choice, but the emergent Gigabit Ethernet may challenge ATM.
   
• Ethernet conforms to the OSI model and covers layer 1 - physical, and layer 2-data link (medium access control).

• Interfaces have been developed to connect all types of computer, across many types of media, to Ethernet. PCs use a network interface card to manage medium access control and communicate with the layer 2 processes.