In another article, I describe how text taken from a book in your library can possibly be used to serve as a one-time pad of sorts, since normal text also contains some unpredictability. The trick is to use a piece of text from an agreed-upon book that is five times the length of the plaintext. That method uses a computer-based hash function, but in this article I tell you how to obtain good security from simple paper and pencil calculations, actually using a key text out of the book that is only three times the length of the plaintext.
BookPad, a paper and pencil “one time pad” cipher
In another article, I describe how text taken from a book in your library can possibly be used to serve as a one-time pad of sorts, since normal text also contains some unpredictability. The trick is to use a piece of text from an agreed-upon book that is five times the length of the plaintext. That method uses a computer-based hash function, but in this article I tell you how to obtain good security from simple paper and pencil calculations, actually using a key text out of the book that is only three times the length of the plaintext.
Absolute forward secrecy
Case scenario: Alice and Bob are emailing messages back and forth between them. They know their email is not secure, so they use encryption to preserve their privacy. Suddenly, SWAT teams break simultaneously into Alice’s and Bob’s apartments. Their respective computers are seized and they are asked at gunpoint for their encryption keys. Can their prior conversation, which has been duly recorded before the break-in, remain private?
Answer: it can, but it requires a very stringent form of secrecy, which I will call Absolute Forward Secrecy (AFS). This is one step beyond Perfect Forward Secrecy (PFS), which is touted a lot these days. In this article, I discuss the different kinds of forward secrecy, and how to obtain the absolute kind with a minimum of hassle. Read More
We’re back!
Yes, the rum
ors of our death were somewhat exaggerated. It all started when our web host, Wizzerwerks.com, disappeared into thin air without any warning around May 23rd. It took all our content down with it, so we’ll see how much can we get back. My hopes are high; after all, doesn’t the NSA have a copy of everything?
Wizzerdwerks was an awesome web host while it lived. The new host is SiteGround, which has high ratings online that seem legitimate. Even better, the files are located in the Netherlands, and if someone were to mess with them this could start a nasty diplomatic situation. This is why the Dutch flag is proudly displayed in this post.