2.1 Plaintext, secret key, ciphertext, and decryption algorithm.2.2 Permutation and substitution2.3 One2.
4 Stream cipher: is scrambles a advanced information stream onebit at a time. Block cipher: is one in which a square of plaintext is treated asa entirety and utilized to deliver a ciphertext piece of break even withlength.2.
5 Cryptanalysis and brute force2.6 the plaintext does not pass through the encryption work, but isXORed with the yield of the encryption work. The math works out that forunscrambling in these cases, the encryption work must moreover be utilized.2.7 aplaintext square is scrambled by passing it through anencryption calculation; the result is at that point passedthrough the same encryption calculation once more; the result ofthe moment encryption is passed through the same encryption calculation athird time. Regularly, the moment organizes employments the decoding calculation Ormaybe than the encryption calculation.2.
8 There is nocryptographic noteworthiness to the utilize of unscrambling for the momentorganize. Its as it were advantage is that it permits clients of 3DES tounscramble information scrambled by clients of the more seasoned single DES byrehashing the key.