3 ms·

I was very confused until I realized this is a wireless system using 4 bits encoding to identify the receiver, but there are 40 households.

jrumbut 7y ago
"4 bits ought to be enough for anybody"
- im3w1l 7y ago
  Even if you think N bits ought to be enough, it should still take pranksters into account.
hoseja 7y ago
Seems to me like the inevitable conclusion to The King's Toaster. https://www.ee.ryerson.ca/~elf/hack/ktoast.html https://www.ee.ryerson.ca/~elf/hack/ktoast.html
- rambojazz 7y ago
  ahahah very spot on!
- yoz-y 7y ago
  To nitpick the story a bit, using time for any kind of cooking is a fire waiting to happen. Use a thermostat, work with temperature. (Same for coffee machines, measure throughput, not time, unless you want your coffees to progressively get smaller as the machine clogs up)
  - huffmsa 7y ago
    Right. The engineer assumes immediate, uniform, consistent heat in the elements. But it's pretty true to life. Ovens and toasters get a bit wonky as they get old.
ginko 7y ago
Maybe you could make it work by carefully setting the IDs so there are no two units within range of each other that are sharing the same ID. Essentially turn it into an extended graph coloring problem.
valdiorn 7y ago
I had a similar experience with a wireless boiler thermostat in our rented terraced house in London. It was one of the more common modules; a cheap one from Wickes or a similar DIY store, so every other house on the street had the same unit. The problem was, they had 3 channels, and (at least) one of our neighbours was using the same, default channel. So his unit would send bogus on/off signals to our boiler, and our boiler unit would turn on and off totally out of sync with what the thermometer reading was. It took me a few weeks to work out this theory (mainly due to the fact that the wires from the old unit were still there, and after giving up on waiting for the landlord to fix it, I tore the unit off the wall only to find that the wires were not connected, only then did I realize it was wireless). I tried changing to a different channel and it all started behaving normally after that. Edit: did I mention that this was costing me well over a hundred pounds a month in excess gas bills? I'm sure someone could come up with a real-world DOS attack with this sort of shit...

jrumbut 7y ago

"4 bits ought to be enough for anybody"

im3w1l 7y ago
Even if you think N bits ought to be enough, it should still take pranksters into account.

hoseja 7y ago

Seems to me like the inevitable conclusion to The King's Toaster. https://www.ee.ryerson.ca/~elf/hack/ktoast.html https://www.ee.ryerson.ca/~elf/hack/ktoast.html

rambojazz 7y ago
ahahah very spot on!
yoz-y 7y ago
To nitpick the story a bit, using time for any kind of cooking is a fire waiting to happen. Use a thermostat, work with temperature. (Same for coffee machines, measure throughput, not time, unless you want your coffees to progressively get smaller as the machine clogs up)
- huffmsa 7y ago
  Right. The engineer assumes immediate, uniform, consistent heat in the elements. But it's pretty true to life. Ovens and toasters get a bit wonky as they get old.

ginko 7y ago

Maybe you could make it work by carefully setting the IDs so there are no two units within range of each other that are sharing the same ID. Essentially turn it into an extended graph coloring problem.

valdiorn 7y ago

I had a similar experience with a wireless boiler thermostat in our rented terraced house in London. It was one of the more common modules; a cheap one from Wickes or a similar DIY store, so every other house on the street had the same unit. The problem was, they had 3 channels, and (at least) one of our neighbours was using the same, default channel. So his unit would send bogus on/off signals to our boiler, and our boiler unit would turn on and off totally out of sync with what the thermometer reading was. It took me a few weeks to work out this theory (mainly due to the fact that the wires from the old unit were still there, and after giving up on waiting for the landlord to fix it, I tore the unit off the wall only to find that the wires were not connected, only then did I realize it was wireless). I tried changing to a different channel and it all started behaving normally after that. Edit: did I mention that this was costing me well over a hundred pounds a month in excess gas bills? I'm sure someone could come up with a real-world DOS attack with this sort of shit...