I'm trying to help a friend with his home network. He has his Sonic router upstairs and someone has run a cable from it to his kitchen (I've tested the cable and it's good). He has a wifi extender placed in the middle of the upstairs but the wifi signal downstairs is very weak. He has mobility challenges, so he prefers to work downstairs. 

  My question is, what is the best device to plug into the kitchen ethernet cable that will deliver strong wifi to the downstairs area? I'm remembering back in the distant past there were Wireless Access Points made by Linksys that did that job. I don't see any around now. I'm also thinking about the routers used for the Sudomesh project that were configured to share some bandwidth publicly. I still have mine -- it is a MyNet N600. But it would need to be reconfigured for my friend's home network (it wouldn't be useful as part of the mesh being downstairs)? Have to admit I've forgotten everything I learned a few years ago about the mesh! :( 

  The bandwidth he's getting from Sonic is only 48 mbps. 

I'd appreciate any advice.

thanks

Hilary