Local Networks and the Internet: From Protocols to Interconnection

Chapter 3

Ethernet and IEEE 802.3 Protocols

The IEEE 802.3 and Ethernet protocols belong to the competition family of protocols. Despite their incompatibility, these two protocols have many common points.

The Ethernet is actually the most frequently used protocol. This chapter shows the protocol evolution and the way it has adapted to the technological advances to remain competitive and in most cases to impose its use.

3.1 History

The Ethernet network had its origin in the Hawaiian Islands at the beginning of the 1970s. The Hawaiian University is distributed over the different Islands. The principal site is on Oahu Island; the other seven campuses are on four islands that compose the Hawaiian state. In order to interconnect the different sites in the 1970s, a system using data transmission through the emission of radio electrical waves was developed.

Every building in each campus had a radio emitter/receiver that transmitted digital data and received data in the same frequency. The transmission speed was 2,400 bit/s. The data block was received by everybody and contained an address in its header, which identified the receiver who was the only one to read the data block. Occasionally several stations transmitted at the same time, producing collisions among blocks. The emission ...