If anyone's wondering "how did cable Internet happen then?" .... a lot of CATV headend gear works on the basis of an RF forward path (downlink) and an optional return-path. DOCSIS and DAVIC are no different.
Add a CMTS at the headend and wire it up to the RFoF TX and RX, and now the customers on that node can access the Internet using a cable modem. It's "just" a fancy TV channel!