|Forms of attack
From the ciphertext of several messages encrypted using the same key, the attacker works backwards in an attempt to
derive either the plaintext or the key.
||An attempt to find the value of a specific key is known as a plaintext attack. Once the key is discovered, a subsequent message sent from the network can be deciphered. In a known plaintext attack, the attacker attempts to derive the key from both the ciphertext and the corresponding plaintext of several messages. A chosen plaintext attack is one in which someone can choose some plaintext but no ciphertext, and then generate encrypted text to derive the key.
|Brute force attack
|| Previously considered slow and cumbersome, in this approach all possible key values are tested by the cryptanalyst until the correct one is found. However, with the rapid increase of processing power and the development of special purpose encryption hardware, brute force attacks have become more prevalent.