I enabled my guest network and put my devices on it so my communications could be separate from the rest of my family on the main network. How can I test this to ensure the guest network really is secure and doesn't interact with any devices on the main network? So far I can tell that my devices are on a new subnet.
I am using a buffalo AC1900 router. I am not sure if they have a good or bad reputation in regards to security. I noticed that the router was secured with WPA-2 AES out of the box and it is secured as default even if you reset the firmware. WPS was enabled but it has a time out function and I could easily disable the WPS option. Wireless guest mode implementation is easily switched on and off and you can enable a second authentication that requires a login to a captive portal before use. One issue I did find is that the login to change settings only allows 8 characters. You can completely disable administration from wireless or wired LAN.