Ethernet: The Definitive Guide, 2nd Edition

Chapter 8. 10 Mb/s Ethernet

This chapter describes the signaling and media components used in the 10 megabit per second Ethernet media systems. We also provide the basic configuration guidelines for both copper and fiber optic cable segments operating at 10 Mb/s.

The original 10 Mb/s Ethernet system was based on coaxial cable segments. There were two kinds of coaxial cable used: the original “thick coax” system, with a cable that was approximately one half inch in diameter, and the “thin coax” system, which used a cable that was roughly one quarter inch in diameter. The thick and thin coax systems used an external medium attachment unit (MAU), also known as a transceiver, to connect the Ethernet interface to the cable.

The connection between the interface and the MAU was called an attachment unit interface (AUI), also known as a transceiver cable. The thin coax interfaces often included an internal transceiver as well, and provided a BNC coaxial connector on the interface for direct connection to the coax, saving the cost and complexity of the external transceiver connection. The external transceiver (MAU) and transceiver cable (AUI) that were part of the coaxial cable systems are no longer used.

The coaxial cable systems are obsolete; all modern Ethernet systems are based on twisted-pair and fiber optic cables. The 10 Mb/s system allows for both, although since the adoption of higher-speed systems the 10 Mb/s fiber optic system is no longer used, making the 10BASE-T system ...