Following an upgrade by the ISP, My parents now have a new modem/router providing a new WiFi network in the upper floor of my their home. (This device is labeled Sagemcom F@ST 3184).
In their lower floor there's an older Edimax BR-6204WG WiFi router that is connected to the new one via a CAT5 cable. The older modem is still providing an older WiFi network (and it's connected to the internet via the Sagecom device)
So I have two WiFi networks at my parents' home and instead I'd like to have just one, shared by both devices.
Is it possible to setup the older Edimax WiFi router to be a part of the same network as provided by the new modem/router upstairs?
If the answer is yes, then how do I set it up?
Which of the following options in the Edimax configuration do I need to choose?