Crypto 101Afterword: This presentation was never actually delivered, however we had several of the CryptKids attendees throw

themselves at the challenge with amazing energy, the kids Young Adults who won this years challenge were amazing.

Next year the challenge will be split into three challenges for different age ranges.

Code or Cipher• Codes are a way of translating language that does not involve

hiding the meaning of the original message usually for digital transmission or brevity

• Examples:

• Morse code: a binary digital code for radio transmission

• Commercial code: special words used to replace entire phrases to save on transmission costs

• Brevity codes: used by militaries for radio transmission

• Base64: used for digital transmission on computer networks

• Ciphers are ways of hiding communications so that only others who have the key can read them

• Examples

• Alberti Cipher (cipher disk)

• Cesar Cipher

• Enigma

Code or Cipher

Every code or cipher has a ‘key’

Cryptanalysis The study of secret codes

• Frequency analysis

• Pattern analysis

For the parents:

Codes and ciphers in media

• Disney XD • TV-Y • Common sense media age

recommendation 8+ • Each episode’s end credits

has a different message • Website dedicated to the

secrets and codes themysteryofgravityfalls.com

• AMC • TV-14 • Common sense media

age recommendation 15+ • There are episodes that

discuss secret messages and different ways of hiding messages. Addresses espionage in historical context

Codes and ciphers in media

Codes and ciphers in media

• PG-13 • Common sense media

age recommendation 13+ • Dramatically fictionalized

history of Alan Turing and the breaking of the Enigma

Codes and ciphers in media

• R • Common sense media

age recommendation 16+ • Addresses issues with

cryptanalysis and how adding a single wheel to the Enigma increase work factor required to solve it.

Codes and ciphers in media

• R • Common sense media

age recommendation 16+ • Fictionalized history of

Navajo Code Talkers

The CryptKids crypto challenge

The next few slides will go through the clues from the challenge. Each decoded message would give you a clue

to how to solve the next message

Welcome to the BSidesDC Cryptkids Crypto challenge. Each puzzle you find will provide you with clues to solve other puzzles so it will be helpful to solve them in order.

For the first puzzle I’ll give you the clue below to help you get started:

Clue: If you had a radio and key you could easily unlock this code

1011 111 001 010 / 10 0 1001 1 / 1010 0100 001 0 / 00 000 111000 / 100 111 10 / 1 / 000 00 1 / 01 10 100 / 011 01 1 1010 0000 / 0010 010 111 11 / 1 0000 0 / 0010 0 10 1010 0 110011 / 110 0 1 / 00 10 / 1 0000 0 / 110 01 11 0 / 01 10 100 / 0000 01 0001 0 / 000 111 11 0 / 0010 001 10

Aemaaectarediir 1 rnha n mtu rporpe rae hscpe n10Fcndaryghctt hi9

Cpo qdaq Anms tva twfpbw vs iu!!!!!!!!n8

WW91IHdvbnQgbmVlZCB0byBzaGF2ZSB0aGlzIEZPVVIgbGV0dGVyIHdvcmQgdG8gZmluZCB0aGUgbmV4dCBtZXNzYWdlIGJ1dCB5b3UgbWlnaHQgbmVlZCB0byB1c2UgaXQgdG8gZmluZCB0aGUga2V5Lgo=

Hi orsh syv fsgiw brg fmtlivw cyx hlbx'w b "wiqb" jsv? B "cyrxmrk-xswwiv" gsiwr'x "xsww xli cyrxmrk" bra qsvi! =

mvnabpm fpb goyqycbma am ywifq bma ykykbtndwv xkgh sllf ynbll yzm dob dsvc ys mqhzf pkb dlmbk tvutskP

13-1-18-25 13-1-18-25 17-21-9-20-5 3-15-14-20-18-1-18-25 25-15-21 19-8-15-21-12-4 8-1-22-5 21-19-5-4 2-5-20-20-5-18 3-15-4-5-19

Since you don’t have access to the wheel I created for the conference use http://www.dcode.fr/alberti-cipher

Set wheels to ABCDEFGHIJKLMNOPQRSTUVWXYZ1234

abcdefghijklmnopqrstuvwxyz1234

2RXKF1JHVTWSN3NMASPMBVQRDSRRELCG42WHXIPGMHZAZGG4KDB

Puzzle SolutionsThe next slides have the solutions and the ciphers used

1) Morse Code: Don’t sit and watch from the fence, get in the game and have some fun

2) Rail Fence: A Frenchman and amateur cryptographer created this cipher in 1901

3) bifid: All your Base are belong to us!!!!!!!!x8 4) Base64: You wont need to shave this FOUR letter word to find the

next message but you might need to use it to find the key 5) Cesar Keyed: Key - head Shift - 4

We know our codes and ciphers but what's a "sema" for?A "bunting-tosser" doesn't "toss the bunting" any more!

6) Semaphore: You’re half way there Have you been playing fair in the CRYPT kids challenge

7) Playfair: numbers are important to codes and ciphers you will need three two and four to solve the final puzzle

8) Numbers: Mary Mary quite contrary You should have used better codes

9) Mary Queen of Scots: spin around 10) Cipher wheel:you have completed the bsidesdc cryptkids crypto

challenge