C pherChess
Group 2:
Adam Glaser
Emilio Lahr-Vivaz
Errol McEachron
Our Idea: Security
Analysis of On-line Evals
Our Surprise
Our Reaction
Our Drinking Buddy
Refused to tell us his real name
Started telling us all kinds of
stories about secret agents, secret codes
and dangerous missions
We all passed out and had a vision…
Our Vision
Yourhallucination
mission, should
This
willyou
selfchoose to
it, is to
destruct
in accept
5 seconds….
discover a method for two
people to communicate in a
hostile environment using an
ordinary device.
MISSION CRYPTOLOGICAL
The Goal: To devise a way that two
people can communicate secret
messages undetected using
readily available materials
Steganography?
Not quite. If detected,
messages must be VERY
secure
Hence…
CipherChess: A scheme for encoding secret
messages using an ordinary chess board and
pieces
Why chess?
-Statistical Properties
-Visible to Everyone
-Confusing enough as it is!
CipherChess Schematic
Pi Plaintext character of message
6

6
Ki Six-bit letter key
6
Ci Ciphertext character
Represent the Ciphertext
character on the chessboard
Column Parity
Definition: For any column on the board, parity is
defined as the number of empty spaces situated
between any pieces modular 2.
A column with no pieces is defined to have parity 0.
A column with one piece is defined to have parity
equal to the number of spaces modular 2 from the
piece to its color’s side of the board.
Example:2:Parity
Example
Parity
==
4 mod
3 mod2 =
2=
01
A Brief Example
Encoding “CS” using key “111111”
Key = 111111
Message – “CS”
000011 010011
Ciphertext 111100 101100
Initial Setting
Key = 111111
Message – “CS”
000011 010011
Ciphertext 111100 101100
First letter –
111100
Parity:
Key = 111111
Message – “CS”
000011 010011
Ciphertext 111100 101100
Second letter –
101100
Parity:
Security Analysis
• CipherChess is steganographic!
• When the number of key bits is greater than
the number of message bits – essentially a
one-time pad
• Using our key selection algorithm, a brute
force testing 1 trillion keys per second
would take 13.5 billion years
In Conclusion
CipherChess
provides
and secure method
Learning about
ciphersa simple
is easy…
for communicating secret messages between two
parties.
Yeah,
DEFINITELY!
right!
But designing them is difficult!
ACKNOWLEDGEMENTS
(In other words, these people were used without their consent)
Dave Evans
Tom Cruise
Portman Wills
Michael Neve
Eric Peeters
Phil Varner
Old Frustrated Man
Errol McEachron