How IoT can betray you

2016 Apr 06

I recently restored a part of my wireless sensor network, and I’m quite pleased of the current state:

  • the sensor part is working
  • the gateway is processing
  • a first chart to visualize what was stored

So after running it for a whole day, I got this chart:

OK, so far it looks great. You can see the sun:

  1. going down in a quasi linear fashion from the beginning to around 6,
  2. then the S transition to night,
  3. then the flat night.

So all good, except for one thing: that big spike in the last part! Guess what it is?

Simply me going into the room and switching the light. As simple as that. In fact I did that experiment on purpose to see how much light difference I would measure (since this measurement is relative – 0 being close to total darkness).

But then it seems rather obvious that if I was to push this kind of stream on internet, anybody would be able to figure out when I’m switching on and off the light … You’re starting to see when I’m going.

So yes IoT is promising a lot of “happy days” but if you want other to track you down in your own home, you have 2 solutions:

  • you don’t publish certain streams and especially the ones coming from inside
  • you “sanitize” some streams by removing any kind of spikes, you basically doctor the data

~ Happy streaming.