SSID Isolation for Guest Network (T3200M) - Chromecast

[wireless]

Hello,

So I have a T3200M where I have a main wifi network running in smart mode so it automatically manages the 2.4/5ghz network for me with the same SSID name, which is great for my office where everyone has the same network/password setup.

Now I also enabled the guest network and set up my office TV on it which will allow office staff and visitors to present on it using a Chromecast, however, it seems Chromecast is only visible and able to connect when the guest network has the "SSID Isolation" disabled. But it does work just fine with the option turned off.

As I understand it, the SSID Isolation is to prevent users on my guest network fro seeing/discovering devices on my primary network and vice versa, but it also seems like it blocks peer/client discovery on the guest network itself. I guess this is by design for a "guest" network for security reasons.

So my main question is: With the SSID Isolation disabled on my guest network, and users being able to see/discover my main network.....is there any point in having the guest network at all? Is it exposing me to a security risk for my main network devices if they're all password protected at the device level?

Are there any benefits other than occasionally updating the wifi password without disrupting my main network connectivity? My home router (Asus) allows my main network to see/discover my guest network, but not the other way around, which would be ideal.


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