The first version of Ethernet was based on coxial cable. The original form of Ethernet 10 Base-5 used a thick Coaxial cable that was not directly connected to the computer’s NIC (Network Interface Card). An attachment unit Interface (AUI) ran from a DB15 connector on the back side of the NIC to the thick coax. A “vampire tap” is inserted into the thick coax to which the AUI is connected. Another version of coaxial cables…"Transmission’s Guided media with Coxial Cable"