Encryption - Blowfish

This algorithm was devised in 1993 and is a symmetric block type cipher. The maker of this encryption method intended it as an “all purpose” algorithm and a replacement for DES, or Data Encryption Standard. BloFish has no patent and is not a commercial, or paid for system, meaning it could be used by anyone, unlike other systems used when he put it together. Its inventor made the statement that no one could ever patent the method and it would be free for all to use forever. It is open source and anyone can use the code to create their own version of the cipher.

The algorithm used in this method is a combination of a few types of encryption. These include a Feistel cipher and S-boxes using a block size of 64-bits and a key length that ranges from eight to 448 bits. The Feistel cipher, of which the BloFish algorithm uses 16 round, is half that of the usual structure because the encoding and decoding schemes are almost identical.

The S-box, or substitution box, is used to hide the information and its relationship to the key used. These items working together produce an output of 32-bits after running through a network of P-array and XOred encryption. If the data input for encoding or data output does not equal at least 8 bytes in length, BloFish will automatically pad the information with extra characters to make it the required length, up to 8 bits.

In producing sub keys, BloFish runs through the entire encryption process 521 times to create them all. Using this method in the exact reverse is the only thing that decrypts the information because it is a Feistel method. Using the XORing, P17 and P18 arrays inverted and adding them to the cipher block than reversing the P-arrays decodes the encryption easily and quickly. The encoding takes more time.

While symmetrical encryption methods are outdated, they still work well. So well in fact that as of May 2010, there has still been no working cryptanalysis found for BloFish. While this method of encoding information cannot be used in every application because it is much slower than others, processing up to 4K of information for each character encoded, it is still used today with some applications.

BloFish is used mainly as a software encryption method, although many hardware components can use it as well. Used as a password manager, its algorithm is a proven effective method of encoding and is perfect for anyone needing to keep people way from personal information. Many software security suites use this method as well as government and military units. As for hardware, there are some limitations, however it is not impossible to implement, although it is slower than some are.
 

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