8 groups of 2 5 rounds Basic Definitions Substitution Cryptosystems Math Tricky Questions Comparing Cryptosystems 10 questions per round.
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CRYPTOGRAPHY TRIVIA
The Game
8 groups of 2 5 rounds
Basic Definitions Substitution Cryptosystems Math Tricky Questions Comparing Cryptosystems
10 questions per round Each question is worth 1 point
Basic Definitions1. Alice and Bob should at some point have
access to a ________ mode of communication.2. Cryptography is only needed when a message
is both _______ and ________.4. To determine how difficult a cryptosystem is
to break, we measure its ________.5. To determine how quickly a cryptosystem
operates, we measure its ________.
Basic Definitions6. _______ is the science of keeping information
secure even though it is transmitted through an insecure medium.
7. _______ is the science of breaking ciphers.8. A _______ is a matching between two different
alphabets.9. To break a cipher means to determine the
______.10. A cryptosystem is made up of five parts:
plaintext space, ciphertext space, encryption function, decryption function, and __________.
Substitution Cryptosystems
1. A substitution cipher uses this to represent its key.
2. A rotation cipher uses this to represent its key.3. An affine cipher uses this to represent its key.4. How many possible keys does a substitution
cipher on have?5. How many possible keys does a rotation
cipher on have?
Substitution Cryptosystems
6. How many possible keys does an affine cipher on have?
7. Encrypt using a rotation cipher over with .8. Encrypt using an affine cipher over with 9. Cipher X consists of a rotation, and then an
affine cipher. What type of cipher is X?10. Cipher Y is a substitution cipher over . Cipher
consists of applying Y twenty-four times. What type of cipher is X? Be as specific as possible.
Math1. Find in .2. Find in .3. Find in .4. Find in .5. Find .6. Solve for and .7. Solve the pair and for and .8. For what is invertible in ?9. Find the prime factorization of 142.10. Find in .
Tricky Questions1. Which of these is a faster growth rate: or ?2. Which of these is a faster growth rate: or ?3. Approximately how many primes are there
between 100,000 and 1,000,000?4. Find a rotation cipher with more keys than a
substitution cipher.5. What is the maximum number of solutions
that can have over . ( are constants, is the variable)
Tricky Questions6. A substitution cipher over has a key sorted by
plaintext. During decryption, how many table-lookups are required in the worst case?
7. A substitution cipher over has a key sorted by plaintext. 4 different characters are encrypted. How many table-lookups are required in the worst case?
8. How many possible Vigenere ciphers over are there that can encrypt exactly 3 characters?
9. A one-time-pad is used on a 5 character message. Oscar figured out the keys, but not the order. In the worst case, how many guesses must be try before deciphering the message?
10. How many factors does 1,000,000 have?
Comparing Cryptosystems1. Among Rotation, Affine, and Autokey, which is
most resistant to a known-plaintext attack? 2. Among Affine, Autokey, and Vigenere, which
can encrypt the fastest?3. Among Affine, Autokey, and Vigenere, which
can decrypt the fastest?4. Which has a larger keyspace? Affine over or
Vigenere over ? 5. Which has a larger keysize? Substitution over
or rotation over
Comparing Cryptosystems6. Which is more secure? Affine or a Vigenere
ciphers?7. Which is more secure? Vigenere or Hill
ciphers?8. Could a computer with 4 processors perform
200 Rotation encryptions or 100 Autokey encryptions faster?
9. Could a computer with 4 processors perform 200 Rotation encryptions or 100 Affine encryptions faster?
10. Which has a larger keyspace? Hill over or Vigenere over ?
CRYPTOGRAPHY TRIVIAThe End
Reference Information Created in the summer of 2013 by Dr.
Jeffrey Beyerl for use in a cryptography class.
This is just a vanilla PowerPoint, but of course like anything you download from the internet: use at your own risk.
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