Re: Smart devices for dummies
That doesn't work well for two reasons. First, this doesn't let you flicker the light however you want. It's not an instant on/off switch. It lets you mess with the device and cause it to malfunction, but not in a deterministic way that produces clean results. If you wanted to do this, your decoding algorithm would have to filter out a lot of noise and you'd have to limit how often you sent your flicker commands, meaning you'd have a really slow baud rate for any transmission you had and you'd need that transmission to contain a lot of error correction. If the lights are on a motion sensor or people turn them off at the wall when they leave, you'd also need to accommodate for it.
Second, the way you flicker the light is to send a radio signal from the device controlling it from a close distance. If you're using that to send data, then you're sending out a signal from the machine that contains the sensitive data. To receive the signal, the receiver needs to be able to detect the light. If you can bring a radio transmitter and a receiver with a camera into the location where the sensitive data is, you can do a much better job by simply sending the data with the transmitter and replacing the camera on the receiver with a radio antenna. You wouldn't need to rely on unspecified behavior from a light bulb or to have security notice you've got a camera on you (if you can take in a camera, you might also try taking pictures of the sensitive data). If you can get the equipment where you need it in order to exploit this, you could already have gotten better equipment in there with fewer requirements.