Almost no one will care about this except me.
And you, if you are actually trying to network a NeXTSTEP computer.
TjLs-Cable-Modem-Howto-for-NeXTStep.pdf is a document I wrote over a decade ago (21 Feb 1998).
It deals with the (at the time) new problem of trying to setup your NeXTSTEP machine to work on one of these new-fangled Cable Modems.
NeXTSTEP didn’t have DHCP, and setting up the networking was complicated enough that I sat down and wrote this up.
I’m putting a copy of it here merely for historical purposes, and the 1/10,000,000 chance that someone is going to hit Google one day looking for instructions like these.
Nowadays it would be pretty simple to setup a static IP for a NeXT behind your home router (note: use 192.168.x.x rather than 192.42.x.x as shown in the PDF :-)