I set up the TL-WPA8630P Kit in my appartment a couple of years ago and it works just fine. Now I would like to extend the network in two additional rooms and installed the clients from this kit: WPA4220T.

To my surpise, the LAN worked right away. I did not have to enter some code or passphrase or anything to connect the new elements with the exisiting ones.

So, my question is, how would I prevent my neighbors to access my network by just plugging in some TP client? What am I looking for to secure the LAN?

Thank you very much in advance.

Bill