[lutusp]

Quote:

"A simple protocol can give us an idea of whether data is being sent to Dropbox:

1. Create a large-ish file (1MB) outside of the Dropbox folder

2. Monitor the network usage of the Dropbox application to see if it sends enough data that it could be that file

3. Repeat with many different files, etc.

Doing exactly that, Dropbox only sent a few hundred KB after “accessing” the target file. Seems unlikely that Dropbox is uploading files outside your Dropbox folder."

This test approach has a problem. A more realistic test would be to place a well-compressed file, one that by definition cannot be made smaller, on Dropbox and see what the system traffic size is for that file. For an optimally compressed file, if the system is reading the entire file, the read size will more or less equal the file size.

[Retric]

You’re still missing the possibility of DB uploading a hash vs standard file compression. Even if they never upload the full file plenty of people would love to know if any of your files was on some list. (Classified information, piracy, etc.)

[darrenpmeyer]

If you read the discussion near the end about why a few hundred KBs, you'll see that the first test file I used was a JPEG embedded in a Word doc (the latter because the original claim used Word files), which should be very difficult to compress.

To be fair, I added this section after several people pointed this out, so you may not have seen it.