Have you ever wanted to send some highly confidential information (like credit card information or root passwords) over the Internet and were afraid others could be sniffing your traffic?. Well, I have, all the time. I've always being paranoid about this, so that's why we, at Insophia, came up with Privnote, a tool for sending private notes over the net in a very easy and secure way.
All you have to do is enter the site, write the note and click Post. Then you get a link that you can send to the only person you want to read it.
What makes it so secure then?.
Two things mostly:
- SSL encryption makes sure the note contents never leaves your browser (neither arrives at the recipient browser) in plain text
- When the note is read (by clicking the link) it automatically self-destructs so no one else who clicks the link could read it. If the note was not read by the intended recipient, at least he/she will known that someone else did it and that the content was compromised
What about the site administrators, you may ask, those ones who always seem to have "full power" over your data. Well, with Privnote, those cannot read your note either. The explanation is a bit more technical, but here it goes: When the note is received by the server, a note ID is created (the same ID you see in the link to read the note). The note contents is then encrypted and saved in the database but (and here's the magic) the salt to encrypt the note is not the note ID but a hash of the note ID. Hashes "one way" so you cannot go back to the note ID from the hash. So the note gets stored in the DB encrypted with a token that only the person which has the note link can read it. Oh, and we also have web server access logs disabled which makes impossible for any administrator to decrypt the note contents. So, as you can see, the only person who has the key to decrypt it is the one who has the link to the note.
As an additional feature, you can get notified when your note gets read, something that (even today) is not possible with any email or instant messaging software.
Also, I want to mention that the application is available in English and Spanish. By default, it works in the language of your browser, but you can change it using the language selector in the top right corner.
I would like to hear your thoughts about it, feel free to post any comment, criticisms and suggestions.