Technical Details

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Encryption Algorithm

 

Cypherix LE uses a 128-bit implementation of the Blowfish algorithm. Cypherix ME, Cypherix PE and Cypherix 10.0 use a 448-bit implementation of the Blowfish algorithm in Cipher Block Chaining (CBC) mode. This ensures that data encrypted using Cypherix is impermeable to all known forms of attack. Statistically, it would be impossible to successfully brute-force crack Cypherix's encryption. Designed by Bruce Schneier, Blowfish is a block cipher with 64-bit block size and variable length keys (up to 448 bits). It has been analyzed considerably and has been proven to be resistant against many attacks such as differential and linear cryptanalysis.

 

Cypherix gives the option of using either blowfish or the new standard- the AES (or Rijndael) symmetric encryption algorithm. Effective May 26, 2002, AES is the official U.S. Government standard. It replaces the previous standard (DES).

 

The new AES meets the following criteria

       - Resistance against all known attacks;

       - Speed and code compactness on a wide range of platforms;

       - Design simplicity.

 

The US National Institute of Standards and Technology (NIST) recommends that AES be used by U.S. Government organizations (and others) to protect sensitive information.

 

How Secure is the AES?

AES is an iterated block cipher with a variable block length and a variable key length.  There are several trillion trillion trillion times that of the AES 128-bit keys and the DES 56-bit keys. In the late 1990s, specialized "DES Cracker" machines were built that could recover a DES key within a few hours. In other words, by trying possible key values, the hardware could determine which key was used to encrypt a message. The chances that someone could use the "DES Cracker" like hardware to crack an AES key are close to zero. Assuming that one could build a machine that could recover a DES key in a second, then it would take that machine approximately 149 thousand-billion (149 trillion) years to crack a 128-bit AES key. To put that into perspective, the universe is believed to be less than 20 billion years old.