Generic Encryption
NAME________________________________ HOUR________
For thousands of years, people have been sending secret messages that have been scrambled so that no person
intercepting the message would be able to read it. This was especially useful during wartime. The process of
scrambling these messages is called encryption. Today with all of the electronic data we have stored in every
part of the world, encryption is more important than ever. It is theoretically possible to break any encryption so
the more complicated the code is, the tougher it is to break. One way to encrypt a message is to use function
composition and function inverse. That is what we will do today.
Space
A
B
C
D
E
F
G
H
First we need to turn all of the letters of the alphabet into numbers.
We will use the chart on the right to do so.
A.
To begin encryption, we need to plug convert a word or
phrase into numbers. Let’s use the word MATH
M=
B.
A=
T=
H=
Write this conversion as a set of points: (M, ) (A,
)(
,
)(
,
0
1
2
3
4
5
6
7
8
I
J
K
L
M
N
O
P
Q
9
10
11
12
13
14
15
16
17
R
S
T
U
V
W
X
Y
Z
18
19
20
21
22
23
24
25
26
)
These 4 numbers given are a sort of code, but it would be really easy to break this code as it is not encrypted. To
scramble the message, we need to perform the same operation to all of the numbers. Pick any operation that
would fit your grade level.
C.
Now perform this operation on each number to create a new set of numbers.
( , )( , )( , )( , )
D.
Represent the entire encryption in bubble form.
M
A
T
H
E.
Write down the bubble form needed to unscramble this message.
F.
Use the inverse operation to unscramble the message.
G.
Convert each of the phrases below into numbers
MR WHITE IS COOL
( , )( , )( ,
( , )( , )( ,
( , )( , )( ,
( , )
H.
)(
)(
)(
,
,
,
)(
)(
)(
,
,
,
)
)
)
YEAH RIGHT
( , )( , )(
( , )( , )(
,
,
)(
)(
,
,
)(
)(
,
,
)
)
Now encrypt the message using an operation of your choosing
__ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __
I.
What do we need to decrypt the message?
J.
Now decrypt each message
__ __ __ __ __ __ __ __ __ __
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G
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0
1
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I
J
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M
N
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9
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R
S
T
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18
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K.
Create your own phrase and choose an operation; then encrypt your message. You will then give your
code and your operation to a member of the class.
Operation:______________
Message:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
Numbers:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
Code:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
L.
Create a second phrase and choose a different operation; then encrypt your message. You will then give
your code and your operation to a member of the class.
Operation:______________
Message:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
Numbers:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
Code:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
M.
Get a code and an operation from a class member and decode the message
Operation:______________
Code:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
Numbers:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
Message:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
N. Get a second code and an operation from a different class member and decode the message
Operation:______________
Code:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
Numbers:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
Message:
___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___