Blowfish is the symmetric block cipher algorithm and it encrypts the block information of 64-bits at a time. It follows the Feistel network and the working procedure of this algorithm is divided into two parts.Subkey Generation − This process transform the key upto 448 bits long to subkeys adding 4168 bits.Data-Encryption − In the data encryption process, it will iterate 16 times of network. Each round includes the key-dependent permutation, and the keyand data- dependent substitution. The operations in the algorithms are XORs or additions on 32-bit words. The only additional operations are four indexed array information lookups per round.Let ... Read More

The Blowfish encryption algorithm is a symmetric block cipher designed to achieve in the DES algorithm that was slow and uncertain. Blowfish is a keyed, symmetric cryptographic block cipher invented by Bruce Schneier in 1993 and located in the public domain.Symmetric encryption uses an individual encryption key to both encrypt and decrypt information. The sensitive information and the symmetric encryption key are used within the encryption algorithm to turn the sensitive information into ciphertext. Blowfish is contained in a huge number of cipher suites and encryption products, such as SplashID.A block cipher is generally a computer routine that takes some ... Read More

The strength of DES is as follows −Use of 56 bit keys56 bit key can be frequently used in encryption. There are 256 possible keys. A brute force attack on such number of keys is impossible.A machine implementing one DES encryption per microsecond would take more than thousands of years to divide the cipher.The assumption of one encryption per microsecond is excessively moderate. Diffie and Hellman postulated that the technology existed to develop a parallel machine with one million encryption equipment, each of which can implement one encryption per microsecond.It is necessary that there is more to key-search attack than ... Read More

There are some popular examples of Block Cipher which are as follows −The CAST Block Cipher − The CAST Block Cipher is an advancement of the DES block cipher, introduced in Canada by Carlisle Adams and Stafford Tavares. The name of the cipher appear to be after the initials of the inventors. The CAST algorithm has 64 bit block size and has a key of size 64 bits.CAST is based on the Feistel structure to perform the substitution permutation network. The authors defines that they need the Feistel mechanism, as it is well considered and free of basic structural weaknesses.Blowfish ... Read More

Weaknesses in Cipher Design − Some weaknesses that have been discovered in the design of cipher are as follows −S-boxes − There are three weaknesses have been discovered in S-boxes which are as follows −In S-box 4, the last three output bits can be changed in the same method as the first output bit by integrating some of the input bits.Two particularly chosen inputs to an S-box array can generate the same output.It is possible to acquire the same output in an individual round by converting bits in only three neighboring S-boxes.D-boxes − One mystery and one weakness were discovered ... Read More

The Data Encryption Standards (DES) algorithm was invented by IBM in the early 1970s. The two main element of the DES-based system are an algorithm and a key. The DES algorithm is a complex interactive procedure includes substitutions, permutations, and mathematical operations.The key feature of DES is that the algorithms is fixed and is public data. But the actual key used is shared secret among the originator and the receiver of a transmission. Advances in DES contains lengthening a key to 128 bits and the multi-pass DES which include multiple passes usually three of encryption and decryption using multiple keys.In ... Read More

A reverse process of encryption is known as Decryption. It is a procedure of transforming Cipher Text into Plain Text. Cryptography need the decryption technique at the receiver side to acquire the original message from non-readable message (Cipher Text).Decryption operate by using the opposite conversion algorithm used to encode the information. The same key is needed to return the encrypted data to its initial state.In decryption, the system extracts and transform the garbled information and change it to texts and images that are simply comprehensible not only by the reader but also by the system. Decryption can be accomplished manually ... Read More

Encryption is a procedure of coding data which can be a file or mail message into cipher text a form unreadable without a decoding key in order to avoid anyone except the pre-determined receiver from reading that information.Decryption is the reverse procedure of transforming encrypted data to its original unencoded form, plaintext. A key in cryptography is a large order of bits used by encryption/ decryption algorithms.In encryption, it is based on the type of encryption, information can be displayed as several numbers, letters, or symbols. Those who work in cryptography fields create it their job, to encrypt data or ... Read More

Data Encryption Standard (DES) is the block cipher which creates a fixed-length string of plaintext bits and change it through a sequence of complicated operations into another cipher text bit string of the similar length. It is a symmetric encryption technique which defines both sender and receiver need a shared key to encrypt and decrypt the information.The problem of this approach is that if the key is known to others the complete conversation is negotiated. The 3DES block size is 64 bits and also need a key to customize the conversion, so that decryption can only be implemented by those ... Read More

TDES stands for Triple Data Encryption Standard. It is upgraded or improved version of DES (Data Encryption Standard) which is a symmetric cryptographic approach in which DES is used to each block three times which scrambles the plain text to cipher text.TDEA provides key size of 56, 112, 168 bits and provide block size up to 64 bits. TDES can be performed with the support of 2 keys and from 3 keys as well. Triple DES runs three times gradual than DES, but is much safer if used properly.The procedure for decrypting object is the similar as the procedure for ... Read More