A long time ago SDSL technology was the new thing. . . it brought high speed internet to thousands of consumers, all using only two wires of the phone line. Fast forward to 2019 and you still may find a need for sending data over phone lines (two conductors). What can you do? Try using a bridge/media converter like the ones they sell at PlanetTech USA. PlanetTech is a local seller (Southern Califiornia) of network technology. This device will allow you to move data over two wires, farther than a mile away! Need a link farther than a mile away? What to do? I am unsure, but usually DSL will also send data farther, yet speeds will decrease. We would have to ask PlanetTech people to be sure.
The BNC / coaxial connection can be used or simply use a connector for your two wire data line. Remember two wire data lines in the world of ethernet are not possible! Let us review, you need at least four conductors to send 100 megabit ethernet data/packets. And recall that the range is? It is limited to a few hundred meters. What about two wires? Using two wires, with HDSL, or VDSL, the range is almost ten times greater!
These VDSL converters will need to be bought as a pair to make a point to point link (or bridge).