While reading articles regarding improving WiFi security, I saw quite a few of them recommend starting Guest WiFi networks.
For instance, see point 4 in the following article:
https://www.techradar.com/news/networking/wi-fi/five-tips-for-a-secure-wireless-network-1161225
One of the commonly cited benefits is that enabling Guest WiFi limits the number of people having access to your regular network. The idea being, only the members of the household will use the regular network and the guests will be isolated to the guest network.
Are there any downsides to this approach? Are there any overlaps between the Guest network and the regular network that an ordinary user should be aware of?
My concern stems from my general lack of education on this matter. To me it seems like creating two doors to the same house. Now I have to worry about securing an additional door, and I haven't properly understood the benefit of having added an extra door.
Edit01:
From the first two answers, I have understood that I should be thinking about the arrangement not as two doors to the same house but as two separate rooms (1 for the regulars and 1 for the guests). In this case is it typical for the router to create two separate 192.168.x.x
ranges? Say for example, can the router serve 192.168.0.123
twice (since the two networks are somewhat isolated)?