WorksheetsCiphers
Total questions: 10
Worksheet time: 5mins
Why is the rotation cipher (ROT-n) so weak? (select all which apply)
Each plaintext letter always maps to the same ciphertext letter
The alphabet is rotated, not randomised, so you once you work out one letter you have the whole alphabet
If, for example, A in the plaintext maps to C in the ciphertext, then A in the ciphertext will also map to C in the plaintext
It was invented by Romans
Using a ROT-1 cipher, encode the word "apples"
bqqmft
nccyrf
lestdg
01101110 01101111
What form of substitution cipher is more secure than ROT-n?
Monoalphabetic substitution
Monopolistic substitution
ATBASH
Navajo
True or false: DECODING a message using ROT-3 is the same as ENCODING a message with ROT-23
TRUE
FALSE
TRALSE
CXIPB
The ROT-n cipher is not used for computer security. Why? Select all that apply
It is insecure
A computer can solve it in seconds
There are only 26 possible versions of the cipher alphabet
It's banned by the FBI
How many different possible ways are there to rearrange the 26 letters in the alphabet?
403291461126605635584000000
26
403291461126605635584
Infinite
Why are monoalphabetic substitution ciphers more secure than rotation ciphers
Because there is no obvious pattern to the cipher alphabet
Because the teacher told us they were
Because the method to decode is different to the method to encode
Because they do not use text
The monoalphabetic substitution cipher is uncrackable. True or False?
True
False
Treu
Falsch
What method is used to try to crack a monoalphabetic substitution cipher?
Frequency analysis
Frequency modulation
Fractional distillation
Amplitude modulation
What are the TWO most frequently used letters in english?
E
T
A
O
I
