A block cipher technique for security of data and computer networks

A block cipher technique for security of data and computer networks is proposed. The technique can be used for text, binary and hexadecimal information. It can be placed in any one of the network layers. It is based on changing the system parameters, starting with the block length, including the number of processing rounds, the used permutation, substitution and arrangement boxes, and ending with a disturbance XOR sequence which is XORed with the final cipher-text block. This makes the system looks like a one-time pad system. These keys are indirectly generated from a text key string either inputted from the keyboard or read from a file. This happens in a delicate way using two input key numbers L/sub 1/ and L/sub 2/ which indicate the orders of the generated keys. The generated keys are used to make all the used parameters changeable from one block to another and from one 8-bit combination to the next. This is done using ElGamal discrete logarithm pseudo-random sequence generators in a special way. Compared with existing techniques, the proposed method offers good properties.