🎧 New: AI-Generated Podcasts Turn your study notes into engaging audio conversations. Learn more

Polygraphic Ciphers: Playfair and Caesar Cipher
24 Questions
0 Views

Polygraphic Ciphers: Playfair and Caesar Cipher

Created by
@RemarkableForsythia

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Cryptography is the art and science of keeping messages public.

False

Decryption is the process of encoding the contents of a message.

False

Cryptanalysis is the art of breaking ciphers.

True

Symmetric key encryption uses different keys for encryption and decryption.

<p>False</p> Signup and view all the answers

Cryptographers are people who practice cryptanalysis.

<p>False</p> Signup and view all the answers

Public-key encryption is a type of symmetric key encryption.

<p>False</p> Signup and view all the answers

Asymmetric Key Encryption uses only one key for both encryption and decryption.

<p>False</p> Signup and view all the answers

Public-key cryptography allows anyone to decrypt a message.

<p>False</p> Signup and view all the answers

Substitution cipher replaces each element of the plaintext with a different element in the alphabet.

<p>True</p> Signup and view all the answers

Monoalphabetic ciphers use different substitutions across the entire message.

<p>False</p> Signup and view all the answers

Vigenère cipher is an example of a polyalphabetic cipher.

<p>True</p> Signup and view all the answers

Product cipher is classified as a transposition cipher.

<p>False</p> Signup and view all the answers

The Playfair Cipher is a monoalphabetic cipher.

<p>False</p> Signup and view all the answers

In the Caesar cipher, each letter is replaced by the letter one position further down the alphabet.

<p>False</p> Signup and view all the answers

The Vigenère Cipher is a polyalphabetic substitution cipher.

<p>True</p> Signup and view all the answers

The keyword 'LEMON' was used to encrypt the plaintext 'ATTACK AT DAWN' in the Vigenère Cipher.

<p>True</p> Signup and view all the answers

In the Caesar cipher, decryption formula is p = (c - k) mod 26.

<p>True</p> Signup and view all the answers

The Vigenère Cipher uses a table together with a keyword for encryption and decryption.

<p>True</p> Signup and view all the answers

In Playfair Cipher, if there is a repeated letter in a pair, a filler like 'Z' is inserted.

<p>False</p> Signup and view all the answers

In Playfair Cipher, if both letters of a pair fall in the same row, they are replaced with the letter above them.

<p>False</p> Signup and view all the answers

In Playfair Cipher, if both letters of a pair fall in the same column, they are replaced with the letter below them.

<p>True</p> Signup and view all the answers

Row Transposition Ciphers involve shuffling the plaintext without altering the actual letters used.

<p>True</p> Signup and view all the answers

Rail Fence cipher involves writing message letters out diagonally over a number of columns.

<p>False</p> Signup and view all the answers

In Rail Fence cipher, if the depth is 3, the ciphertext is read off vertically instead of row by row.

<p>False</p> Signup and view all the answers

Study Notes

Cryptography Basics

  • Cryptography is the art and science of keeping messages secret, not public.

Encryption and Decryption

  • Decryption is the process of decoding the contents of a message, not encoding.
  • Symmetric key encryption uses the same key for both encryption and decryption.
  • Asymmetric Key Encryption, also known as public-key encryption, uses a pair of keys: one for encryption and another for decryption.

Cryptanalysis

  • Cryptanalysis is the art of breaking ciphers, not making them.

Cryptographers

  • Cryptographers are people who practice cryptography, not cryptanalysis.

Ciphers

Substitution Ciphers

  • Substitution cipher replaces each element of the plaintext with a different element in the alphabet.
  • Monoalphabetic ciphers use a single substitution across the entire message.
  • Polyalphabetic ciphers use multiple substitutions.
  • Vigenère cipher is an example of a polyalphabetic cipher.

Transposition Ciphers

  • Product cipher is classified as a transposition cipher.
  • Row Transposition Ciphers involve shuffling the plaintext without altering the actual letters used.
  • Rail Fence cipher involves writing message letters out diagonally over a number of columns.

Specific Ciphers

Playfair Cipher

  • The Playfair Cipher is a monoalphabetic cipher.
  • In Playfair Cipher, if there is a repeated letter in a pair, a filler like 'Z' is inserted.
  • In Playfair Cipher, if both letters of a pair fall in the same row, they are replaced with the letter above them.
  • In Playfair Cipher, if both letters of a pair fall in the same column, they are replaced with the letter below them.

Vigenère Cipher

  • The Vigenère Cipher is a polyalphabetic substitution cipher.
  • The Vigenère Cipher uses a table together with a keyword for encryption and decryption.
  • The keyword 'LEMON' was used to encrypt the plaintext 'ATTACK AT DAWN' in the Vigenère Cipher.

Caesar Cipher

  • In the Caesar cipher, each letter is replaced by the letter one position further down the alphabet.
  • In the Caesar cipher, decryption formula is p = (c - k) mod 26.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Description

Learn about polygraphic ciphers, specifically focusing on the Playfair and Caesar cipher. Understand how the Playfair cipher substitutes two-letter groups, and how the Caesar cipher shifts each letter by a fixed number of positions.

More Quizzes Like This

Polygraph Examination Preparation Tips
18 questions
Polygraphy and Psychophysiology Quiz
11 questions
Polygraph Test Overview and Procedure
8 questions
Use Quizgecko on...
Browser
Browser