5 ms·

The key insight is that the drone should store the video to local storage for later (1) recovery or (2) buffered encrypted transmission to the mother ship which

The key insight is that the drone should store the video to local storage for later (1) recovery or (2) buffered encrypted transmission to the mother ship which would eliminate the leakage of clues about what subject is being spied upon.

cavanasm 9y ago
The problem with that is the video feed is being actively used. If you want to know where someone is going, you can't just make your drone fly around randomly for hours recording video of the area you think they're in, you have to visually acquire your target, and then follow them.
- deleted 9y ago
  [deleted]
lb1lf 9y ago
Buffered transmission is unlikely to help; after all, the surveillance target could store the received stream and look for patterns - it would only delay detection for the length of the buffer (which often would need to be kept short due to the real-time nature of much surveillance. Granted, you could obfuscate things by varying the buffer length and padding the data stream (as suggested near the end of the article) - but at some point, a high-value surveillance target will probably just assume that a nearby drone is probably not operated by an avid bird-watcher or something like that and just blast the drone out of the sky. (Preferably using a laser or better still lots and lots of microwave RF - tends to get the surroundings less aggravated than using a shotgun...)
- alistproducer2 9y ago
  >Granted, you could obfuscate things by varying the buffer length and padding the data stream Or maybe sending the blocks out of order to be reconstructed according to a shared ordering key?
  - yjftsjthsd-h 9y ago
    I don't think that helps with metadata analysis? Assuming I'm following correctly, we're already encrypting, so it shouldn't matter what order we send... Unless you mean to shift around bandwidth spikes, which could help some
yarg 9y ago
Buffering doesn't eliminate the VBR issue, it just obfuscates it in a breakable way. The fix is a constant bitrate with a sensible block cipher mode.

cavanasm 9y ago

The problem with that is the video feed is being actively used. If you want to know where someone is going, you can't just make your drone fly around randomly for hours recording video of the area you think they're in, you have to visually acquire your target, and then follow them.

deleted 9y ago
[deleted]

lb1lf 9y ago

Buffered transmission is unlikely to help; after all, the surveillance target could store the received stream and look for patterns - it would only delay detection for the length of the buffer (which often would need to be kept short due to the real-time nature of much surveillance. Granted, you could obfuscate things by varying the buffer length and padding the data stream (as suggested near the end of the article) - but at some point, a high-value surveillance target will probably just assume that a nearby drone is probably not operated by an avid bird-watcher or something like that and just blast the drone out of the sky. (Preferably using a laser or better still lots and lots of microwave RF - tends to get the surroundings less aggravated than using a shotgun...)

alistproducer2 9y ago
>Granted, you could obfuscate things by varying the buffer length and padding the data stream Or maybe sending the blocks out of order to be reconstructed according to a shared ordering key?
- yjftsjthsd-h 9y ago
  I don't think that helps with metadata analysis? Assuming I'm following correctly, we're already encrypting, so it shouldn't matter what order we send... Unless you mean to shift around bandwidth spikes, which could help some

yarg 9y ago

Buffering doesn't eliminate the VBR issue, it just obfuscates it in a breakable way. The fix is a constant bitrate with a sensible block cipher mode.