Thanks for quick reply.
Yes the wifi
router have 4 RJ45 ports but if I move it to ground floor then there is almost no range in some of my rooms on 1st floor.
I don't know much about switch, can it solve the problem? Because the wifi router will assign one ip to the lan port to which it is connected (because only one cable is coming down to ground floor). How will it work?:welcoming:
Yes, a switch will solve the problem, I will 100% confirm that.
The router doesn't assign an IP address to the LAN port (only managed devices do that, so unless you've spent a couple thousand dollars on yours, it's not managed), it assigns an IP address to the device(s) which are connected.
A switch is kind of like a splitter, but slightly more intelligent. You can technically connect as many devices as you like to each of yours router's LAN ports using multiple small switches or a few big ones, though that would become a horrible hodge-podge of un-manageability very quickly - so by "as many as you like" we really mean "as many as you like within reason" - but for you this is not a concern.
In your case, since there would be two devices connected, both the desktop PC and the
printer will get an IP address each, and the only thing is that the bandwidth on the cable going upstairs is shared between your PC and the printer.
And I'm not talking that each device gets half the bandwidth (as mentioned, it's a little more intelligent than that) but that both devices are capable of using that single cable at the same time thanks to the switch.
(Excuse the bad explanation, but I'm too lazy to think of a better way to word it right now).