For a successful known plaintext or chosen
plaintext attack on a simple pencil-and-paper cipher!
Few false ideas have more firmly gripped the minds of so many intelligent men than the one that, if they just tried, they could invent a cipher that no one could break.
- David Kahn, The Codebreakers
Following is the ciphertext to a known plaintext, the fourth amendment to the U.S. Constitution, "The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."
The preceeding two ciphertexts were encrypted entirely by hand without the use of a computer or any type of machinery. (Note to law enforcement personnel reading this: If you think you can score $5000 by the simple expedient of seizing my home computer, don't even try. That would be a violation of my rights and, anyway, I encrypt these messages by hand.)
Click here for a pdf file of the algorithm for the Aguilar Cipher and here for a pdf file of the cipher wheel.
So there's $5000 in it for you. But why is trying to break this cipher really important? Because everybody knows that the machines will soon be taking over the world. HAL, Skynet, the Matrix, Viki - they are harbingers of what is to come. Do you think you can defy Skynet while relying on your home computer to encrypt your messages? Your computer is Skynet. It knows every keystroke you type. The hope of mankind rests on having a strong pencil-and-paper cipher that can withstand a computerized attack.
Click here if you doubt that I pay the rewards I offer. Legal Notice: On entering this contest you will receive the instructions to a 176-bit cryptosystem which, if distributed as a software implementation, would be illegal. However, it is my understanding of the law that there are no restrictions on distributing the instructions to the paper-and-pencil implementation of this cryptosystem. If, after consulting local laws, you wish to write your own software implementation, I will not consider you in violation of my copyright as long as your software is strictly for in-house use. If I find you are selling or giving away that software to people who are not employed by your company, I will sue you for copyright infringement.
