I've seen a team demonstrating an idea of broadcasting an emergency beakon to all the devices connected to a wifi access point without authentication. they claim that they can send upto 27,XXX bytes of data!
I tried to contact them regarding this but didn't get any response.
In the same way i found mobile carriers like att and verizon, instaling updates on the mobile devices of their users to send emergency alerts.
I'd like to try it out as well. I tried searching on google and looking for research papers but found none.
Does anyone have any idea about how to achieve this?