INTRODUCTION: Blowfish, a symmetric block cipher developed by Bruce Schneier[SCHN93, SCHN94), is a Feistel network, iterating simple encryption and decryption functions of 16 times each. The block size is 64 bits, and the key can be any length up to 448 bits. Although there is a complex initialization phase required before any encryption can take place, the actual encryption of data is very efficient on large microprocessors. Blowfish was designed to have the following characteristics: Fast: Blowfish encrypts data on 32-bit microprocessors at a rate of 18 clock cycles per byte. Compact: Blowfish can run in less than 5K of memory. Simple: Blowfish's simple structure is easy to implement and eases the task of determining the strength of the algorithm. Variably secure: The key length is variable and can be as long as 448 bits. This allows a tradeoff between higher speed and higher security. Blowfish encrypts 64-bit blocks of plaintext into 64-bit blocks of ciphertext. Blowfish is implemented in numerous products and has received a fair amount of scrutiny. So far, the security of Blowfish is unchallenged. DESIGN DECISIONS Based on Schneier's design parameters, he have made these design decisions. The algorithm should: - Manipulate data in large blocks, preferably 32 bits in size (and not in single bits, such as DES). - Have either a 64-bit or a 128-bit block size. - Have a scalable key, from 32 bits to at least 256 bits. - Use simple operations that are efficient on microprocessors: e.g., exclusiveor, addition, table lookup, modular- multiplication. It should not use variablelength shifts or bit-wise permutations, or conditional jumps. - Be implementable on an 8-bit processor with a minimum of 24 bytes of RAM (in addition to the RAM required to store the key) and 1 kilobyte of ROM. - Employ precomputable subkeys. On large-memory systems, these subkeys can be precomputed for faster operation. Not precomputing the subkeys will result in...

...Image Encryption Using Block-Based Transformation Algorithm
Abstract:Encryption is mainly used to transmit the data over networks. There are so many techniques introduced which are used to protect the confidential image data from any unauthorized access. Multimedia data contains different types of data that includes text, audio, video, graphic,images with the increasing use of multimedia data over internet, here comes a demand of secure multimedia data. Most...

...A
TERM
PAPER
ON
“BlowfishEncryption Algorithm“BLOWFISHENCRYPTION ALGORITHM”
WRITTEN BY
NDIFON, PATRICK MANYOR
10/50050
COMPUTER SCIENCE
UNIVERSITY OF CALABAR
SUBMITTED TO
DR. F.U. OGBAN
COURSE LECTURER
IN PARTIAL FUFILMENT OF THE COURSE REQUIREMENT
CSC4211
SEPTEMBER 2014
TABLE OF
CContentsONTENTS
1. Introduction
2. Origin/Founder
3. Algorithm/Data Structures
4. Category/Performance:
5. Pseudocode
6....

...network. Date encryption is, in its simplest terms, the translation of data into a secret code. In order to read an encrypted file, the receiver of the file must obtain a secret key that will enable him to decrypt the file. A deeper look into cryptography, cryptanalysis, and the Data Encryption Standard (DES) will provide a better understanding of data encryption.
Cryptographic Methods There are two standard methods of cryptography, asymmetric...

...International Journal of Engineering Research & Technology (IJERT)
ISSN: 2278-0181
Vol. 3 Issue 4, April - 2014
Evaluation of DES, TDES, AES, Blowfish and
Two fish Encryption Algorithm: Based on
Space Complexity
MD Asif Mushtaque
Harsh Dhiman
M.Tech(CS&E)
School of Computing Science and Engineering
Galgotias University, Greater Noida, U.P .
M.Tech(CS&E)
School of Computing Science and Engineering
Galgotias University, Greater Noida, U.P....

...to searchsecurity.techtarget.com, “Encryption is the conversion of data into a form, called a ciphertext that cannot be easily understood by unauthorized people.” In order to understand the data or the message that is being sent, the receiver must be able to decrypt the message. Decryption thus refers to the process of converting the message from cipher text into its original format or plaintext whereby the reader would be able to understand the message. Encryption...

...using a common key. In addition, for devices that can’t be secured
physically, practical (side-channel, reverse engineering) attacks will likely take
precedence over cryptanalytic ones. The point is that there is a price to be
paid (with every encryption) for blocking purely theoretical weaknesses, and it
makes sense to think about what price is justiﬁed.
Since there is not yet a fully crystallized point of view on this issue, we have
proceeded in a more-or-less standard...

...Data Encryption Standard
In 1972, the NBS Institute for Computer Sciences and Technology (ICST) initiated a project in computer security, a subject then in its infancy. One of the first goals of the project was to develop a cryptographic algorithm standard that could be used to protect sensitive and valuable data during transmission and in storage. Prior to this NBS initiative, encryption had been largely the concern of military and intelligence organizations. The...

...Contemporary Symmetric Ciphers
(Double-DES, Triple-DES & Blowfish)
Supervised by:
Dr Loái Tawalbeh
Eng. Sulaiman Al-Basheer
Simsam R.Hijjawi
20022171043
Review Problems:
6.1 What is the triple encryption?
It is a three-stages encryption with three different keys, to avoid costly requirements arises from using three different keys with total length of 3x56 = 186 bits a triple encryption...

875 Words |
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