A NOVEL APPROACH TO INCREASE THE STRENGTH OF THE ROUND KEYS USING INITIALIZATION VALUE (IV) WITH KEY FORWARD METHOD IN ENHANCED SECURE DATA ENCRYPTION STANDARD (ES-DES)

The Data Encryption Standard (DES) was a well-known symmetric key block cipher algorithm. It was the most popularly used in different applications like banking, online trading, and online transactions, etc., as well as unsafe, because the 56-bit key size is small compared to the other cryptographic algorithms, and possible to a hacker can attack using brute-force techniques with a modern processor. In most cases, 128- bit symmetric keys are sufficient. The Enhanced Secure Data Encryption Standard (ES-DES) algorithm uses an initial 96-bit key instead of the originally used 56-bit key. The proposed system has a modified round key generation algorithm uses Initialization Value(IV) with Round Key Forward techniques, which is completely different from the original DES. The result of the design is an ES-DES-variant cryptographic system that has a strong avalanche effect, produces greater resistance to brute force attack. So, the results demonstrate that the proposed scheme possesses a very large round key space to resist the brute-force attack and it is much protected to statistical attacks and linear cryptanalysis