Cryptology in practices

Running head: Cryptology in practices
Cryptology in practices
Name of the Student
Name of the University
Author Note

Cryptology in practices 1
Question 1:
A 0
B 1
C 2
D 3
E 4
F 5
G 6
H 7
I 8
J 9
K 10
L 11
M 12
N 13
O 14
P 15
Q 16
R 17
S 18
T 19
U 20
V 21
W 22
X 23
Y 24
Z 25
a)

Cryptology in practices 2
Cipher text: VYEHVCWIQTBGUFKTMWOVQUNB
Key; k = (2, 17, 24, 15, 19, 14)
Plain text: THIS COURSE IS SOMETIMES FUN
b)
Chosen key: image
c)
Plain text: He is a good person
Cipher text: Pqiyeoaojtmdsur
Question 2:
a)
n= 659041
n-1 = 25×3×5×1373
m = 3×5×1373 = 20595
b = 2^20595 mod 659041 = -1
So, the number 659041 is not a prime.
659041 is divisible by 743 and 887. So it is not a prime number.
b)
n = 657412
a = 2, B = 50
b0 = a