Slide 1

Confederate Cipher Disk Simran, Lovjoat, Arshdeep, Zohaib TEAM SALL-E

Slide 2

History Cipher Disks were invented by Leon Battista Alberti, a famous Italian philosopher and architect in 1467. Fundamentally, involving two rotating rings that line up two different letters or numbers which ciphers the text. (Cipher meaning a method of altering the plaintext) Used during Civil War At the rear of the disc is the text Richmond, VA, the home town of the confederacy.

Slide 3

History Cont. Vigenre Cipher was simple enough to use to be a field cipher. Used during the American Civil War (1861-1865) The war between the North (Union) and the South (Confederates) Union usually cracked the confederates messages.

Slide 4

Creator Francis LaBarre, a gold and silver worker Based on the Vigenre Cipher A mechanical wheel cipher consisting of two concentric disks, each with the 26 letters of the Latin alphabet, that was used for the encryption of messages.

Slide 5

Purpose The disk was used for encryption of secret messages of the Confederacy during the American Civil War (1861-1865)

Slide 6

Key Short key phrase said in a private previous conversation A polyalphabetic cipher disk that was a combination of the Caesar Cipher and the Vigenre Cipher

Slide 7

Examples R is the default adjustment letter and key number 1212, the inner disk turns so that R and the number 1212 coincide The signal adjustment 2212, 3, 1122, 333, indicates W was adjustment letter, and 1122 the key number completing the cipher combinations (W coincides with 1122) -Note: 2212 being W in the non-ciphered code

Slide 8

Only five are known today in existence.

Slide 9

The Navajo Code Talkers

Slide 10

History Philip Johnston realized that the Navajo languages was very complex and was not written down. The code was used for troop movements, tactics, order, and transmit info, with the use of native dialects over radios and telegraphs. The language was primarily used during WWII, Korean war, and was retired after the Vietnam war. On May 1942, 29 recruits attended boot camp and was the first group that made the code.

Slide 11

Creator Philip Johnston proposed the idea to use the Navajo language as code during WWII Chester Nez, last of the original Navajo Code talkers of WWII dies at 93.

Slide 12

Purpose During WWII the allies needed an encryption they realized that Navajo language was very difficult The navajos would say random words and then write their english equivalent and would use 1 st letter to make a word.

Slide 13

Examples wol-la-chee ( a nt), tse-nill ( a xe) tsah ( n eedle) be-la-sana ( a pple) ah-keh-di-gini ( v ictor) Tsah-ah-dzoh ( y ucca) Besh-lo (iron fish) meant submarine Dah-he-tih-hi (humming bird) meant fighter plane

Slide 14

How the Code was Broken Most letters had more than one Navajo word representing them. Not all words had to be spelled out letter by letter. developers of original code assigned Navajo words to represent about 450 frequently used military terms that didnt exist in Navajo language

Slide 15

Reference http://www.cryptomuseum.com/crypto/usa/ccd/index.htm http://www.cryptomuseum.com/crypto/usa/ccd/index.htm http://www.nsa.gov/kids/ciphers/ciphe00005.shtm http://www.nsa.gov/kids/ciphers/ciphe00005.shtm http://www.history.navy.mil/faqs/faq61-2.htmhttp://www.history.navy.mil/faqs/faq61-2.htm http://navajocodetalkers.org/navajo-code-talkers-facts/http://navajocodetalkers.org/navajo-code-talkers-facts/