I don't see how this is any significant improvement over just having passphrase protected private key in your dropbox. In both cases some cloud server has similar access to encrypted keyfile.
Users will choose 'password'; they'll choose '12345'; they won't choose 'VPSJjNwytizY7vtGzRv208' or 'cZD2N49caaSYkDuWZMHuyiuKuk6AhA5jdC29g3moHmX' (128- and 256-bit, respectively).
> You don't need completely new protocol for that.
You need a protocol because protocols can be audited and built upon. User-interaction protocols are very much a part of crypto and, IMHO, trying to minimize the user-error surface is critical for cryptography's development.
This is about bringing crypto to the average Joe. You think they're going to download several heterogeneous tools, learn to use them, devise their own security protocol... and also not mess anywhere in the process? I don't think so!
If a protocol+app saves them the hassle and lowers the chance of mistakes, why not?
Also, as they point in the article:
> One could simply throw out the last 30 years of protocols like SMTP, IMAP and PGP and reinvent the wheel like DarkMail, but we at Whiteout believe in building on existing standards, since they aren't going away any time soon.
This would merely be another layer at the stack.
No, of course not. User-memorable passwords should only be used on devices physically controlled by the user or someone the user trusts; high-security passwords must be used on any device outside of the user's control.
It's okay to use the user's password to locally encrypt a secure key used to encrypt remote data.