Ethernet

Ethernet is a fundamental family of wired networking technologies. It is used to connect computers in various environments. These environments include local area networks (LAN), metropolitan area networks (MAN), and wide area networks (WAN).

Because it is an open standard, many different manufacturers can build equipment that works together. This openness has made Ethernet a key technology for the modern Internet. It carries much of the Internet Protocol traffic used globally today.

To move data, Ethernet systems use a specific communication process. A continuous stream of data is divided into smaller pieces called frames. Each frame contains a source address and a destination address. This ensures the data reaches the correct recipient. Frames also include error-checking data to protect the information. If a frame is damaged, the system can detect and discard it.

Often, higher-layer protocols will then trigger a retransmission of the lost frame.

The logic of Ethernet is based on a method called Carrier-Sense Multiple Access/Collision Detection, or CSMA/CD. This concept evolved from an earlier radio network called ALOHAnet. Designed by Norman Abramson in the late 1960s, ALOHAnet was used at the University of Hawaii. In ALOHAnet, a sender would resend a message after a random wait if it was not received. Ethernet improved this by requiring a sender to listen to the channel first. The sender checks if the channel is in use before transmitting. This helps prevent data collisions on the shared medium.

Ethernet has undergone many physical transformations over the decades. The original version, known as 10BASE5, used a thick coaxial cable. This was later replaced by 10BASE2, which used a thinner and more flexible coaxial cable.

Modern Ethernet typically utilizes twisted pair cabling or fiber optic links. These modern connections often work alongside network switches to manage traffic.

Switches allow for multiple simultaneous data transmission paths. This is a significant upgrade from the older shared communication channels. In 1993, the introduction of full-duplex mode potentially doubled transmission rates.

The history of Ethernet is a story of competition and cooperation. In 1972, Robert Metcalfe and David Boggs adapted ALOHAnet for coaxial cables at Xerox PARC. Their first successful run occurred on May 22, 1973, at a rate of 2.94 Mbps. Metcalfe chose the name "Ethernet" to suggest it could run over any medium. Later, Metcalfe, Gordon Bell, and David Liddle pushed for standardization. They convinced Digital Equipment Corporation, Intel, and Xerox to create the DIX standard.

This collaboration resulted in the Ethernet Blue Book in 1980. By 1983, the IEEE 802.3 standard was officially published, making Ethernet a global open standard.

Market competition helped drive the technology into homes and offices. In 1979, Metcalfe founded 3Com to sell Ethernet adapters for personal computers. 3Com's EtherLink adapter was a major success because it used VLSI semiconductor technology. This allowed most functions to fit on a single chip, lowering the price to $950.

While IBM supported its own Token Ring protocol, 3Com's adapter worked on IBM PCs. This helped Ethernet expand rapidly as IBM shipped 200,000 units a month by 1982. Later, Novell's sale of its NE2000 network interface cards helped drive prices down even further.

Ethernet continues to evolve to meet the demand for higher speeds. Data rates have increased significantly since the early 10 Mbps days. In the 1990s, Fast Ethernet emerged to provide 100 Mbps speeds.

Since 1999, the technology has reached even higher levels. These include Gigabit Ethernet, 10 Gigabit Ethernet, and 100 Gigabit Ethernet. Engineers are even working on Terabit Ethernet. This constant growth ensures that Ethernet remains a vital part of our digital infrastructure. It connects everything from small home setups to massive industrial systems.