High speed

hi new to this sight and have no idea how to post something on my own so here i am.I was wanting to know about cable high speed,when got my cable high speed the installer just took the modem right out of a new box hooked right to my tv cable line and i had highspeed  he did nothing extra to my computer just turned on the box.So i was thinking that because all you need is that box from a cable line can i just buy my own box and plug it in our is way more to it?

Well, there’s the little matter of what happens on the other end of that line, at the cable company.

It’s not like you could get away with buying a modem and then not paying subscription fees.

ah yes