[inigyou]

It is. This is what they mean by an aether - a wire connecting several computers so that any of them can send an electrical signal they will all receive. Ethernet was named after this, but doesn't use an ether any more.

In this design you need a way to make computers take turns. CSMA/CD is the stupidest: wait until nobody is transmitting before you transmit, and if two nodes start transmitting at the same moment, both abort.