Date Added: Feb 2012
In this paper, a session based symmetric key cryptographic system has been proposed and it is termed as Bit Shuffle Technique (BST). This proposed technique is very fast, suitable and secure for encryption of large files. BST consider the plain text (i.e., the input file) as binary string with finite no. of bits. The input binary string is broken down into manageable-sized blocks to fit row-wise from left to right into a square matrix of suitable order. Bits are taken diagonally upward from the square matrix to form the encrypted binary string and from this string cipher text is formed. Combination of values of block length and no. of blocks of a session generates the session key for BST.