1	11															13
2
							3
	4
				12
			5
6
			7
8
			9
10

Across

1. A technique used to analyze and decipher encrypted messages by studying the frequency of occurrence of letters or symbols in the ciphertext.

2. A method of encrypting alphabetic text using a series of different Caesar ciphers based on the letters of a keyword.

3. A polygraphic substitution cipher that uses a 5x5 table containing a keyword or phrase to encrypt pairs of plaintext letters.

4. A monoalphabetic substitution cipher in which each letter in the plaintext is shifted a certain number of places down the alphabet.

5. A cipher that rearranges the order of the plaintext letters or symbols, rather than replacing them with different ones as in a substitution cipher.

6. The study and practice of breaking codes and ciphers, usually with the goal of deciphering encrypted messages without knowledge of the secret key.

7. A mathematical operation that finds the remainder when one integer is divided by another. The Vigenere Cipher uses this operator to perform its encryption and decryption operations.

8. A cipher that uses multiple substitution alphabets to encrypt the plaintext. The Vigenere Cipher is an example of this type of cipher.

9. A cryptanalytic technique used to try and discover the length of the keyword used in a Vigenere Cipher by detecting repeating patterns in the ciphertext.

10. "A polyalphabetic cipher similar to the Vigenere Cipher, but using the plaintext itself as part of the key sequence in order to overcome a weakness observed in the original Vigenere Cipher."

Down

11. A transposition cipher that is created by writing the plaintext horizontally in a zigzag pattern, and then reading off the ciphertext vertically.

12. A cryptanalytic technique that involves trying every possible key until the correct one is found. This is usually only feasible for small key sizes.

13. A cipher that replaces each plaintext letter or symbol with a different letter or symbol to create the ciphertext.

🖶