How does chosen plaintext attack work?

A general batch chosen-plaintext attack is carried out as follows: The attacker may choose n plaintexts. The attacker then sends these n plaintexts to the encryption oracle. The encryption oracle will then encrypt the attacker’s plaintexts and send them back to the attacker.

What are the steps to encrypt a message using Playfair cipher approach?

Playfair Cipher Encryption Rules

1. First, split the plaintext into digraphs (pair of two letters).
2. After that, break the plaintext into digraphs (pair of two letters).
3. To determine the cipher (encryption) text, first, build a 5*5 key-matrix or key-table and filled it with the letters of alphabets, as directed below:

What is adaptive chosen message attack?

An adaptive chosen-ciphertext attack (abbreviated as CCA2) is an interactive form of chosen-ciphertext attack in which an attacker first sends a number of ciphertexts to be decrypted chosen adaptively, then uses the results to distinguish a target ciphertext without consulting the oracle on the challenge ciphertext, in …

What is a chosen key attack?

Chosen-key attacks are a bit different than other kinds of cryptographic attacks. Usually, he knows exactly what keys have been used or he himself can choose the secret key. An example of a chosen-key attack can be a situation when an intruder tries to compromise a hash function based on a block cipher.

What is encryption process?

Encryption is a process that encodes a message or file so that it can be only be read by certain people. Encryption uses an algorithm to scramble, or encrypt, data and then uses a key for the receiving party to unscramble, or decrypt, the information. In its encrypted, unreadable form it is referred to as ciphertext.

What is the rule for encryption in Playfair cipher if the letters in a pair does not appear in same row or column?

Explanation: If the letters in a pair does not appear in same row or column then they are replaced by the letters of the same row at the corner of the rectangle defined by the original pair respectively. The order of letters should be maintained.

How do you solve Hill cipher problems?

3) Hill Cipher Decryption

1. Step 1: Calculate the multiplicative inverse for the determinant.
2. Step 2: Value for Adjugate Matrix.
3. Step 1: Calculating the multiplicative inverse for the Determinant.
4. Step 2: Calculate the Adjugate Matrix.
5. Step 3: Finalising the inverse matrix value.

How do you implement Hill cipher in Java?

HillCipherExample.java

1. import java.util.ArrayList;
2. import java.util.Scanner;
3. public class HillCipherExample {
4. //method to accept key matrix.
5. private static int[][] getKeyMatrix() {
6. Scanner sc = new Scanner(System.in);
7. System.out.println(“Enter key matrix:”);
8. String key = sc.nextLine();