Shift Cipher Concepts and Decryption

This tutorial explains the shift cipher, often called the Caesar cipher, and demonstrates how to encrypt and decrypt messages by shifting the cipher text alphabet. It covers the concept of plain text and cipher text alphabets, the process of shifting, and how to perform encryption and decryption with different shift values.

What is another name for the Shift Cipher?

• Transposition Cipher

• Substitution Cipher

• Caesar Cipher

• Vigenère Cipher

In the context of the Shift Cipher, what is the relationship between the original and cipher text alphabets?

• They are completely unrelated

• The original alphabet is reversed

• They are identical

• The cipher text alphabet is a shifted version of the original

What happens when you shift the cipher text alphabet to the left?

• Each letter encrypts to the previous letter

• The alphabet is reversed

• The alphabet remains unchanged

• Each letter encrypts to the next letter

If you encrypt the letter 'T' with a shift of one, what does it become?

• T

• V

• U

• S

What is the maximum shift value before the cipher text alphabet returns to its original form?

• 24

• 25

• 27

• 26

What is the first step in decrypting a cipher text?

• Guessing the shift value

• Reversing the text

• Identifying the shift used

• Using a different cipher

When decrypting with a shift of three, what does the letter 'U' revert to?

• T

• Q

• R

• S