Introduction to Ethernet Technology

For many years, Ethernet has proven itself as a relatively inexpensive, reasonably fast, and very popular LAN technology. This tutorial explains the basic functionality of Ethernet and how it can be utilized on home and business networks. 

History of Ethernet

Engineers Bob Metcalfe and D.R. Boggs developed Ethernet beginning in 1972. Industry standards based on their work were established in 1980 under the IEEE 802.3 set of specifications. Generally speaking, Ethernet specifications define low-level data transmission protocols and the technical details manufacturers need to know to build Ethernet products like cards and cables. Ethernet technology has evolved and matured over a long time period. The average consumer can generally rely on off-the-shelf Ethernet products to work as designed and to work with each other.

Ethernet Technologies

In the OSI model, Ethernet technology operates at the physical and data link layers - Layers One and Two respectively. Ethernet supports all popular network and higher-level protocols, principally IP. 

Traditional Ethernet supports data transfers at the rate of 10 Megabits per second (Mbps). Over time, as the performance needs of LANs have increased, the industry created additional Ethernet specifications for Fast Ethernet and Gigabit Ethernet. Fast Ethernet extends traditional Ethernet performance up to 100 Mbps and Gigabit Ethernet up to 1000 Mbps speeds. Although products aren't yet abvailable to the average consumer, 10 Gigabit Ethernet (10000 Mbps) also remains an active area of research. 

Ethernet cables likewise are manufactured to any of several standard specifications. The most popular Ethernet cable in current use, Category 5 or CAT5, supports both traditional and Fast Ethernet. The Category 5e (CAT5e) cable supports Gigabit Ethernet. 

To connect Ethernet cables to a computer, a person normally uses a network adapter, also known as a network interface card (NIC). Ethernet adapters interfaces directly with a computer's system bus. The cables, in turn, utilize connectors that in many cases look like the RJ-45 connector used with modern telephones.