Q: What are your long-term plans? How will you react to legal pressure?
A: We'd like to create a file storage and sharing service with a similar security approach.
In case of legal prosecutions, we can't hurt users because we don't know anything about them, and we can't decrypt their notes.
Q: Why is this better then Evernote?
A: Evernote is far from secure, and their Privacy Policy says that your notes may be viewed where necessary 'to comply with our legal obligations, such as responding to warrants, court orders or other legal process.'
Q: Do I have to use a long password?
A: You don't have to, but it's recommended. The longer the password, the harder it is to guess it. Note that your text is protected by both the URL and your password.
Q: Can I use a suspicious internet connection (e.g. Starbucks)?
A: Yes. Your password (or password hashes) are never sent over the network, and all data that's sent or received is always encrypted. Your data is decrypted only on your device, and encrypted before it's returned to us.
Q: How can you verify that a password is correct if you don't store it anywhere and don't send it to server? How do you authenticate the user?
A: The server doesn't know anything about authentication; that's all handled in your browser. There are no users on ProtectedText.com, just sites. Passwords are never saved; not even within encrypted text.
Decryption of a page will fail if the password is incorrect, so whoever can decrypt the page must have used the correct password. The idea is that we don't have to know the password; we just have to make sure that the password is correct - and one way to check that is to try decrypting some well-known text using the provided password. The "well-known" text we're using is the URL of the current site (which is different, but known, for each site).
Once a user creates the password, we store the encrypted URL, and each time the password needs to be tested, we just try decrypting the encrypted URL. If we get the expected URL, we try using the same password for decrypting the whole site (it's possible -- but very unlikely -- that two different passwords correctly decrypt the same URL, but using that wrong password for decrypting everything else will result in gibberish).
Q: How does overwrite protection work?
A: Overwrite protection prevents you from saving any changes if text was changed in the meantime. (The server stores the hash of the newest content, and sends the hash to the client together with the content. The client has to return that same hash when trying to save updated content. The server compares both the stored and received hashes to determinate whether client was served with the latest changes.)
Q: How is the title of each tab computed?
A: The title of each tab consists of up to 20 characters from the first non-empty line of text.
Q: What encryption algorithms are used?
A: ProtectedText.com uses standard AES algorithm for encrypting/decrypting the content, together with 'salts' and other known good practices to achieve exceptional security; and SHA512 algorithm for hashing. On top of that, all data is only provided through SSL.
Q: Is the server code available somewhere? I'd like to host the service myself.
A: We haven't opened the server code, for now. We'd like to provide perfect security to everyone, not just tech users. So we've created this approach where server side is irrelevant - that's the beauty of this service.
Nobody should be forced to trust anyone in order to be secure; that's why all security is provided from the client side (which users can verify). Even if you knew the server code, you couldn't confirm whether that code was running on server, or if it was replaced by something else. In other words: whenever a server's code is responsible for providing security, you have to trust whoever runs it.
Q: How long do you keep sites on your servers? Will they ever expire?
A: Sites aren't deleted automatically. We'll keep them until you delete them yourself.
Q: Is there a length limit?
A: The current maximum length is a bit more then 750 000 chars per page.
Q: Is there some kind of self-destruct mechanism?
A: All that we have are encrypted versions of notes that you store on our servers, so once you delete your notes, that's it; there is nothing more to destroy.
