4. Physical support for native 10 Mbps Ethernet

4.1 10Base5: coaxial support and its first industrial variant SINEC H1

10Base5 is Ethernet's native physical medium, supporting a transmission speed of 10 Mbit/s over the famous 10 mm thick coaxial cable, also known as yellow cable because of its color. The identifier "10Base5" is a contraction of the baseband transmission speed of 10 Mbit/s and the maximum segment length of 500 m. Stations are connected to the coaxial cable by means of a transceiver, or MAU (Medium Access Unit), mounted on the coaxial cable, and another cable called a drop cable to attach the station to the transceiver. For this purpose, stations have a 15-pin Sub-D connector called AUI (Attachement Unit Interface).