Assume you have internet service. Modem and Main router is in Room 1. Assuming that I don't want to do any kind of mesh networking, can I simply plug in another modem into the wall/coax of Room 2?
I'll have to pay for additional modem service, yes no? (my own modem, none of that rental crap to the cable company).

Also, does splitting a coax cable degrade service/speed/quality? In cable TV or Internet speed?

You would have to have two internet accounts to use a second modem. Why not just run an ethernet cable to the other room?

We're debating all our options might consider Dish or similar instead.
Here's the scenario. Main House, Detached garage with pain cave (read: TV), and separate Mother in Law tiny house.
Trying to get cable service to MIL tiny house, BUT they have to run the cable underground, which is a definite no no for us. We have sprinklers, a septic, water and electricity between the main house and the MIL tiny house.
Digging through "JUST" for cable TV is not worth it. I'm 110% we'd hit something even being super careful.

One option we're considering is running coax to the garage BEHIND all those aforementioned utilities, from the main house. Then Pain Cave would have cable, and run coax from the other side of the garage to the tiny house (digging only 4 inches or bare minimum) so that we only cross one sprinkler line.

Hence the reason for my question. If I have coax, can I put a second modem in the tiny house through the coax. If needing second account, that seems overkill. So might run coax AND CAT5 at the same time digging from the garage to the tiny house. Basically brainstorming at this time.

Well, if you are going to bother running ethernet, don't run CAT5. CAT6. Hell, there might be a 7 by now, I haven't kept up on that.

Yes good looking out. I wasnt sure what the "generic" name for wired internet of the latest standard. Ethernet escaped my mind.

Does it have to be wired?

Signal boosters might be your answer. Kinda mesh-network-lite. Plug-in signal repeaters. https://www.linksys.com/us/p/P-RE7000/ or eq.

I guess cable tv is more important than internet for MIL. In the case of cable, seems they say it MUST be run underground.

Dish network has recently dropped some spanish channels. Seems I'll look into DirecTV and or keep spectrum plus a bit of labor.

Two modems would require two subscriptions. The modem is the connection to your ISP.

You could plug in another router but that creates two networks. You could use a switch which basically splits up your existing network.

You can run a modem (Docsis 2.0 modems have 2 ethernet outlets actually) and then a wifi router into that modem, then another wifi router in parallel (and then plug ethernet connections into that second router).

At least, I think you can.

Are you referring to MoCa? Never tried but have used Powerline Networking; similar technology I guess.

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