The Grille Cipher
-----------------

The Grille Cipher falls into the Transposition Cipher category. A
transposition cipher is a plaintext message which is manipulated in such
a way as to display a secret cipher text within it. For a good example,
I refer to the movie Red Dragon, part of the Hannibal series. Hannibal
writes letters to a newspaper editorial column, which Red Dragon then
reads, and using a grid, can select only the words of importance...

It is important to note that this is not a computer based for of
encryption. It is all done on paper. There is no algorithm that can
decode a grille ciphered message. It is interesting to note that it was first used and developed around 1550 AD.

Ok, now that we know that, I will show you how to make secret messages
for whatever purpose you choose. Be it sending love notes in class, or
correspondence with your hired hitman

Lets make us a plain sounding message:


I think the flowers
in spring are worth
a moment, to have
a sniff and take in
the wonders of nature.
Life is not long enough
to waste hours beating
around silly shops.


Ok, so thats our rather random message that would mean nothing special
to the average Joe that picks it up... But, if you had a grid that
looked like this:

____________________
| |_|     _                      |
|         |_|                     |
|              _                  |
|   _        |_|                 |
|  |_|   _                    _ |
|_      |_|             _   |_||
|_|         _          |_|      |
|______|_|____|_|_____|


You or the person you are communicating with would take this grid, place
it over the text and the gaps would highlight the following letters:

t + a + k + e + o + u + t + b + u + s + h

which is made neater into the message

"take out bush".

The perfect way to hide a very illegal, criminal message in an open area
without anyone suspecting you. This form of encryption is not used any
more except for puzzles and maybe the lame computer puzzle game, but
they did serve their purpose many years ago. If you want to be different
and basically guarantee confidentiality, go ahead and use this method
because no-one bar the most determined cryptographer in the world will
bother to decrypt your message

I hope this has been an interesting tutorial, and that it helps develop
your understanding and comprehension of some of the possible encryption
techniques available.

Happy Cracking!

invas10n

[Ask the experienced, not the learned]