Sunday, November 8, 2015

Secret Codes and Cryptology

Introduction

For as long as writing has existed, there have been secret codes and cyphers.  There has been a need to send messages that are intended to be kept private or secret.  As long as there have been secret codes, there have also been people who try to break these codes to learn those secrets

There are also codes that are not secret, such as Morse Code that uses dots and dashes to represent letters and numbers.  This was the primary method of sending messages across long distances quickly in the days before telephones allowed us to use our voices.  Braille and Sign Language are also codes used to allow people who cannot see and/or hear to communicate using touch or there hands.

Cub Scout Achievements






NOVA Award 1, 2, 3 Go!: Requirement 4

4- Secret Codes
a-     Look up, then discuss with your counselor each of the following:
1-     Cryptography
2-     At least three ways secret codes or ciphers are made
3-     How secret codes and ciphers relate to mathematics
b-    Design a secret code or cipher. Then do the following:
1-     Write a message in your code or cipher.
2-     Share your code or cipher with your counselor.



Wolf Elective Adventure: Code of the Wolf: Requirement 4


4- Do one of the following:
              a. Use a secret code using numbers to send a message to one of your den members or your den leader. Have that person send a message back to you. Be sure you both use the same code numbers.
               b. Send a message to another member of your den or your den leader using the pig pen code or another code that changes letters into special shapes.
               c. Practice using a code stick to create and decode a message.






Tiger Adventure Elective: Curiosity, Intrigue, and Magical Mysteries: Requirements 4 and 5

4- Create a secret code.
5- With the other Scouts in your den or with your family, crack a code that you did not create.

Discussion

Some examples you can use to demonstrate codes with the boys include the following:
Morse Code- There is a great application though Boys Life that teaches Morse Code.  Though this is largely obsolete, hobbyist in Amateur Radio still use it as means to communicate (they call it CW) and the military, pilots and sailors also still learn it as a back-up communication if they lose voice communications.

            Here is the Link to the Boy’s Life Application for Morse code

Enigma and Ultra- The German Enigma machine was used in World War 2 and due to the complexity of the machine, and the fact the settings were changed every 24 hours, it had up to 159 million million million (1,590,000,000,000,000,000) combinations!




To demonstrate this with the boys I obtained a digital version of the machine that was developed by STGEOTRONICS (http://www.stgeotronics.com/Enigma-Replica_c3.htm ).  Though this is expensive, it was a fun project for me to build and it really gets the point across to the boys.




Less expensive (e.g. less than $10 or Free) alternatives are a Windows application (https://www.microsoft.com/en-us/store/apps/enigma-machine/9wzdncrdgkzd  ); web application (http://enigma.louisedade.co.uk/ ); and/or iPad application (https://itunes.apple.com/us/app/mininigma-enigma-machine-simulator/id334855344?mt=8 )

Discussion

For the boys, to meet the requirements listed above, a simpler and doable code is needed.  For this I recommend the following items that are easy to prepare and for them to figure out and have fun.  These are all easy to make and do.

1-  Caesar Wheel- This is also known as a shift cypher.  The easiest one is where you have a inner and outer wheel and the letters around the wheel are still in Order (e.g. A, B, C…).  This is a good one to have them try to break.  For the requirement, they need to make their own code so using the following wheels where the letters need to be added to the inner wheel (make sure they do not duplicate letters, I recommend having them check off the letters as they put them in).

Here is a template for your use from an on-line teacher resource:

2-    Grid Cypher- This is also known as a transposition cipher.  It is simply a grid that correlated letters with a letter number combination.

KEY




EXAMPLE

D        O           Y        O       U      R           B       E        S        T
2E      1C         5E      1C      D1    2B         2D     2A      1A     1E

3-    Code Stick- To make a code on a code stick, you need a long strip of paper, and a walking stick or a broomstick.  First you wind the strip of paper tightly around the broomstick.  Then you write your message all the way down the stick (you can write it on several lines).  When you unwind the message, no-one can read it unless they have the same stick as you! But if they have the stick, they can read the message just by winding the strip of paper around it again.


4-    Pig Pen- Also known as the Masonic Cipher or Tic-Tac-Toe cipher.  This uses grids and symbols to create the key and those symbols to create the code that the key deciphers.

KEY




EXAMPLE

      




This should give you everything you need to teach the boys secret codes and ciphers.  Have fun!