New approach for modifying DES algorithm using 4-states multi-keys

الملخص EN

Within the last decade, there has been a vast increase in the accumulation and communication of digital computer data in both the private and public sectors.

Much of this information has a significant value, either directly or indirectly, which requires protection.

One of the most important protection methods is inventing and developing different encryption algorithms.

The algorithms uniquely define the mathematical steps required to transform data into a cryptographic cipher and also to transform the cipher back to the original form.

This paper introduces a new method to enhance the performance of the Data Encryption Standard (DES) algorithm.

This is done by replacing the predefined XOR operation applied during the 16 round of the standard algorithm by a new operation depends on using two keys, each key consists of a combination of 4 states (0, 1, 2, 3) instead of the ordinary 2 state key (0, 1).

This replacement adds a new level of protection strength and more robustness to breaking methods.