The Data Encryption Standard (DES) is a symmetric key block cipher which creates 64-bit plaintext and 56-bit key as an input and makes 64-bit cipher text as output. The DES function is create up of P and S-boxes. P-boxes transpose bits and S-boxes substitute bits to make a cipher.DES is ... Read More

DES is a block cipher. The encryption procedure is create of two permutations (Pboxes) that it can be defined initial and final permutations, and 16 Feistel rounds. Each round need a different 48-bit round key created from the cipher key according to a pre-represented algorithm. The DES function uses a ... Read More

There are two main variations of Data Encryption Standard are as follows −Double DES − Double DES is an encryption approach which need two instance of DES on same plain text. In both instances it uses multiple keys to encrypt the plain text. Both keys are needed at the time ... Read More

There are various elements of DES which are as follows −Use of S-Boxes − The tables used for substitution i.e., the S-boxes, in DES are kept hidden by IBM. IBM supports that it took them over 17 person years to appear up with the internal design of the S-boxes.Key Length ... Read More

This operation expands the right half of the information, R from 32 bits to 48 bits and this operation changes the order of the bits as well as repeating specific bits. It is called an expansion permutation.This operation has two objective including it creates the right half the similar size ... Read More

DES uses 16 rounds. Each of the 16 rounds includes the broad-level steps are as follows −Key Transformation − An initial 64-bit key is changed into a 56-bit key by discarding each 8th bit of the initial key. Therefore for each round, a 56 bit key is available. From this ... Read More

An initial permutation is required only once at the starting of the encryption process. In DES, after the complete plaintext is divided into blocks of 64 bits each, IP is required on each of them. This initial permutation is a phase in the transposition procedure.The initial permutation appears only once, ... Read More

A cryptographic hash function is a transformation that creates an input (or message) and restore a fixed-size string, which is known as the hash value. A hash value h is produced by a function H of the form −h = H(M)where M is the variable length message and H (M) ... Read More

A cryptographic hash function is a numerical function used in cryptography. A cryptographic hash function integrate the message-passing capabilities of hash functions with security features.The term hash function has been used in computer science from quite frequently and it define as a function that compresses a string of arbitrary input ... Read More

DES is a block cipher. The encryption procedure is create of two permutations (Pboxes) that can be defined initial and final permutations, and 16 Feistel rounds. Each round need a different 48-bit round key produced from the cipher key in accordance with a predefined algorithm.DES is based on the two ... Read More