Backchannel: computers can talk to each other with heat




So this communications channels runs at .001 bits per second? As in it could transmit a 2048-bit private key (with no metadata) in about 19 days?


The time it took them to increase the heat and transmit a “1” varied
between three and 20 minutes depending. The time to restore the system
to normal temperature and transmit a “0” usually took longer.

As a ‘prototype’, it can be done. Advances in the technology will certainly speed things up. Moore’s Law holds that a computer will be able to provide fiber equivalent speeds in a couple of months. Zoom!


Slow, but if you logged user login IDs and passwords, you wouldn’t need much data to prepare for a compatriot on premises to gain access.


Hooray! We’re now applying Moore’s law to thermal-dynamics!


Seems like some sort of Peltier cooling would speed up this process.


Infrared communication? Where have I heard of this before.


Isn’t it about a week early for this?


It’s in the Palm™ of your hand.


Changing temperature would involve varying the fan speed. Wouldn’t it be more efficient to just use the sound or vibration of the fan. If the other computer has a mic, it would be trivial to detect the noise.
Imagine having a rack of computers, you could theoretically transmit a signal to all of the server simultaneously. If you are listening for a very specific signal on a very specific frequency, you can filter out all the noise.
You wouldn’t even need to use a computer to be the transmitter. You could have a tampered cell phone use a special ringtone to activate the infected computers. Or the phone system, or intercom. You would think that it was just glitching out, but it would really have the instructions embedded.


This topic was automatically closed after 5 days. New replies are no longer allowed.