During spelling correction, there is not any need for any data to leave your computer. In fact, the spelling correction on this text box is a feature of your browser, not of news.ycombinator.com.
The whole point about serving targeted ads is aggregating multiple sources of data to build an extensive "customer" profile.
In addition to sensor-based collision avoidance you would probably want some means of communication between the drones so they can choose non-colliding flight paths in advance.
In the altitude these drones will be flying most of the regular traffic probably is composed of helicopters. For those Amazon could easily provide some means of requesting a temporary drone no-flight zone.
I think tree branches will be a rather large problem for these drones since you need a pretty high resolution 3D sensor to accurately detect them.
GPS is most certainly not enough for navigation next to a building since you can hardly get an accuracy below 5m. I would bet on navigation by computer vision and 3D sensors.
Another interesting aspect of this is the choice of location where to drop the package. You certainly would not appreciate finding your emergency math textbook in the middle of your flower bed. This could for example be solved by setting up delivery spots in advance, or perhaps by using human judgement through something like Amazon's Mechanical Turk.
This could for example be solved by setting up delivery spots in advance, or perhaps by using human judgement through something like Amazon's Mechanical Turk.
You'll just get your Amazon Prime Beacon™ which you just put on the floor and sends out little pulses to guide the drone.
Instead of a battery-powered beacon you would likely use fiducials [0].
The issue I see with delivery to windows is all the clutter that is commonly found in front of windows such as power lines, tree branches etc. since that cannot yet be easily detected with computer vision and inexpensive 3D sensors.
I would seriously advise anybody from using this device. Designing a hardware true random number generator takes a lot of effort that this design is evidently lacking. For example, there is no whitening whatsoever. Even worse, the firmware includes a line of code that ensures that the "RNG" never outputs the same "random" number twice in a row.
Also, usually HW RNGs include a firmware module that is constantly monitoring the entropy output and shutting off the generator in case of it sinking below a certain threshold to detect hardware failure and prevent it from causing predictable output.
Some more information on this subject can be found at Wikipedia: https://en.wikipedia.org/wiki/Hardware_random_number_generat...
I do not want to discourage anybody from working on such things. I think this is a nice project idea and a very good opportunity to learn a lot about random numbers. Please, though, always put a big warning on any crypto things you designed youself and do not present them as a finished product.
> Also, usually HW RNGs include a firmware module that is constantly monitoring the entropy output and shutting off the generator in case of it sinking below a certain threshold to detect hardware failure and prevent it from causing predictable output.
This sentence reminded me of the recent revelation of some smartcards:
Afaik the failure was exactly that there was insufficient HW failure detection.
edit:
> Even worse, the firmware includes a line of code that ensures that the "RNG" never outputs the same "random" number twice in a row.
Also this reminds me of another anecdote. In math/stats class teacher told us of a experiment where two people were to write a 100 digit random sequence of 0s and 1s on a paper. One person was to use a coin flip, an the other was to just make the bits up. Then the person administering the experiment would take the sequences and guess which one was true random (coin flipped) and which one was human-generated. The trick being that humans tend to avoid repetition, and the one with (iirc) 6 consecutive 0s or 1s was most likely true random.
That's only assuming that the PRNG hasn't been backdoored or otherwise compromised by the NSA. If it has, damn near ANY hardware RNG will be better than it. If not, then you're right.
They claim to be a "non-profit" organization organizing community events.
I think it was not very intelligent on their part to (according to their post) try to finance themselves by effectively trademark-trolling community events.
When you allow less common tools to be used, one could use the bash or zsh read-builtin to read the master password without echoing (e.g. dash's read can not do that) and use xclip or similar to directly put the password into the X clipboard. With xclip's -l option you could even automagically "forget" the clipboard after it was pasted once.
The python scripts to generate the repository from the xmls freely available from the german government is also on github:
https://github.com/bundestag/gesetze-tools
So, go ahead, hack! ;)
The whole point about serving targeted ads is aggregating multiple sources of data to build an extensive "customer" profile.