Crossloop Screen Sharing Encryption
All of the data transferred between the Share and Access computers is encrypted / decrypted using the Blowfish symmetric encryption algorithm developed by Bruce Schneier (http://www.schneier.com/). Blowfish is a variable-length key block cipher. The key length used by CrossLoop is 128-bits and the algorithm is a 64-bit block cipher.
Blowfish is a block-encryption algorithm designed to be fast (it encrypts data on large 32-bit microprocessors at a rate of 26 clock cycles per byte), compact (it can run in less than 5K of memory), simple (the only operations it uses are addition, XOR, and table lookup on 32-bit operands), secure (Blowfish's key length is variable and can be as long as 448 bits), and robust (unlike DES, Blowfish's security is not diminished by simple programming errors).
The Blowfish block-cipher algorithm, which encrypts data one 64-bit block at a time, is divided into key-expansion and a data-encryption parts. Key expansion converts a key of at most 448 bits into several subkey arrays totaling 4168 bytes. Data encryption consists of a simple function iterated 16 times. Each iteration, called a "round," consists of a key-dependent permutation and a key- and data-dependent substitution. |
