I had several iterations of this in S. Fla.--first "MediaOne" 1-way cable (downlink via a General Electric Sufboard SB-1000
ISA card with uplink via modem), then an external SB-1200 which was a combination cable modem downlink and modem uplink and an ethernet gateway. Finally, they threw all that away and gave us a DOCSIS modem.
I still remember what a pain it was to get that 1-way modem working on linux. I had to print the documentation out from Windows, and then reboot. On the other hand, learning how to get that driver[1] to compile and loaded as a kernel module was very educational.
[1] https://github.com/torvalds/linux/blob/master/drivers/net/sb...