I recently saw [this video](https://www.youtube.com/watch?v=Ed1OjAuRARU), in which some students attached an 'attack kit' to a drone and flew it near office blocks. 

According to [their paper](http://iotworm.eyalro.net/iotworm.pdf):

> 
> We managed to
>  tie a fully autonomous attack kit below a standard drone,
>  and performed war-flying in which we flew hundreds of
>  meters away from office buildings, forcing all the Hue lamps
>  installed in them to disconnect from their current controllers
>  and to blink SOS in morse code
> 
> 
> 

They then go on to say:

> 
> We
>  use results from percolation theory to estimate the critical mass
>  of installed devices for a typical city such as Paris whose area
>  is about 105 square kilometers: The chain reaction will fizzle
>  if there are fewer than about 15,000 randomly located smart
>  lamps in the whole city, but will spread everywhere when the
>  number exceeds this critical mass (which had almost certainly
>  been surpassed already)
> 
> 
> 

Although it's an interesting thought, I'm not sure whether this is really likely. They say that a reasonable range for the bulbs is 100 m, but later note *"The Philips engineers we talk with stated that in a dense urban
environment, the effective range can be less than 30 meters"*. I reran their formula with [that figure](http://www.wolframalpha.com/input/?i=%3D+(1.128(105,000,000))%2F(%CF%80(30%2F2)%5E2)) and came out with needing about 168,000 bulbs.

On the other hand, if we go with the 'optimistic' estimate of 400 m, the formula predicts that you'd need [less than 1000 bulbs](http://www.wolframalpha.com/input/?i=%3D+(1.128(105,000,000))%2F(%CF%80(400%2F2)%5E2))!

Obviously, the 400 m estimate is *very* optimistic, so I'm not inclined to trust it much, especially considering all the radio interference that's likely to be around in an urban environment. [Philips](http://www2.meethue.com/en-us/support/faq-categories/product/hue-bridge/) only promise 'up to 30 m' range, so 400 m seems incredibly optimistic.

**Is the 'chain reaction' idea unrealistic/slightly exaggerated?** It seems to me to just be an attention-grabbing headline, if my calculations are correct. Is there any evidence to show that the range of the bulbs is nearer 100 m, and hence the chain reaction idea is possible?