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ES-DES) Algorithm Using Extended Substitution Box (S-Box International Journal of Applied Engineering Research ISSN 0973-4562 Volume 12, Number 21 (2017) pp.11365-11373 © Research India Publications. http://www.ripublication.com Enhanced Secure Data Encryption Standard (ES-DES) Algorithm Using Extended Substitution Box (S-Box) T.K.Sivakumar Research Scholar, Research and Development Centre, Bharathiar University, Coimbatore – 641 046, Tamil Nadu, India. Assistant Professor (Sr.Gr), Department of Master of Computer Applications, SRM University, Chennai, Tamil Nadu, India. Orcid: 0000-0002-6166-2695 Dr. T.Sheela Professor & Head, Department of Information Technology, Sri Sai Ram Engineering College, Chennai, Tamil Nadu, India. Dr. R.Kumar Professor, Department of Electronics and Communication Engineering, SRM University, Chennai, Tamil Nadu, India. Orcid: 0000-0001-6745-5214 Dr. K.Ganesan Professor, Department of Mathematics, SRM University, Chennai, Tamil Nadu, India. Orcid: 0000-0002-4532-0222 Abstract original contents[1]. Cryptography system provide different types services other than encryption and decryption, such as In general, the strength of any cryptographic algorithm depends on the key size, number of rounds, and robustness of • Checking integrity—recipient check that the original S-Boxes against cryptanalytic attack. The Data Encryption message has not altered during transformation. Standard (DES) is a block cipher cryptographic system, which • Authentication — verifies the uniqueness of a user or provides the security in the banking sector, cloud computing process. but nowadays the development in DES calculation power seems weak against brute-force attacks. DES algorithm it A readable message is called plaintext. The scrambled or accepts an only 64-bit block of plaintext and key. So the unreadable information is called cipher text[2]. The process of cryptanalysis they can easily find out the original value of the converting from readable message to unreadable message is key using brute-force attacks. In this paper, we proposed the known as encryption. The process of converting from Enhanced Secure Data Encryption Standard (ES-DES) unreadable message to readable message is known as Algorithm Using Extended Substitution Box (S-Box) is to decryption. In Fig. 1 illustrates the overall process of support and improve the security of DES algorithm. To encryption and decryption. improve the security of the DES by increasing a size of the key as well as creating and extending the robust S-Boxes before the ES-DES algorithm to complete the process using Enhanced Secure DES (ES-DES) algorithm. While extending S-Boxes and increasing the key size, the security of the ES- Figure 1: Encryption and decryption process DES algorithm is improved against cryptanalytic attacks and confusion makes the use of the key so complex, it is still difficult to deduce the key. Cryptanalysts(from the Greek kryptós, "hidden," and analýein, "to loosen" or "to untie) attempt to capture ciphertext during Keywords: DES, S-BOX, Avalanche effect, hamming transformation to find the original plaintext without weights knowledge of key or the algorithm. The algorithm and a secret value are involved in the INTRODUCTION ABOUT CRYPTOGRAPHY cryptographic systems. The secret value is known as a key. The strength any algorithm is based on the key size or secret Cryptography comes from the Greek words κρυπτο ("hidden value. With a good cryptographic system is perfectly or secret") and γραφη ("writing"). It is the one the techniques acceptable for everyone, including the poor (and cryptanalyst) used for secret writing. Normally, cryptography as the art of know the algorithm because anyone can use the algorithm. translate from one format to another format and it is mainly But the algorithm does not allow disassembling information used to transfer the information from one participant to others without knowledge of the key. The concept is similar to a in a secure manner, otherwise during the transformation the combination of keys for a combination lock. intruders or hackers can capture the data and understand the 11365 International Journal of Applied Engineering Research ISSN 0973-4562 Volume 12, Number 21 (2017) pp.11365-11373 © Research India Publications. http://www.ripublication.com It is important that the encryption algorithms are reasonably 40 and 48. When you add design criteria, this distribution efficient that the asset can calculate. The good ones are those evolved in a range of 52 to 59. The left tail of the distribution who have knowledge of the keys. Without knowledge of the was chosen To minimize the size of the DES implementation key is it very difficult to break cryptographic algorithms. The in the hardware. The goal is to check this statement in the hackers or intruders can try all possible keys until finding the hope that it can shed light on the generation of S-DES blocks. original plaintext or key is known as brute-force attacks. The First, we generated a large number of S-blocks that meet security of a cryptographic system based on key size and IBM's design criteria published in 1994 godu; This was more algorithm[3]. If the large key size and more complicated difficult than expected. algorithm are there, which take more than 10 million years to break then, it can be considered reasonably safe all the computers in the world. ENHANCED SECURE DATA ENCRYPTION With the help of encryption device or computers can be used STANDARD (ES-DES) for an exhaustive key search. Computers they do not get tired Nowadays DES is used in different applications like banking, and are much faster than people, even if encryptor tried with online trading, and online transactions, etc., as well as unsafe, large key size. Parallel processor is used to solving the because the 56-bit key size is small compared to the other complex problem; it can split into smaller modules, which is cryptographic algorithms, and possible to a hacker can attack to used to save the time. Some cryptographic algorithm to use using brute-force techniques with a modern processor. So, the variable length[4]. Whenever the implement more key size, new Enhanced Secure DES (ES-DES) scheme of a symmetric which provides more safer than other algorithms. Increasing key algorithm with a DES 128-bit key is proposed. In any the length of the key a bit works good guy a little more cryptographic algorithm, if the size of the key is very small complicated, but does the job twice as hard as the bad guy. then it won't provide more security because the intruder can easily find the original information duration the transformation between the sender and receiver. Hence, DATA ENCRYPTION STANDARD proposed algorithm ES-DES algorithm might be protected Publication of the DES algorithm in 1977 by National Bureau from the intruders and others. Therefore, improving the of Standards (NBS) in USA has been surrounded by security of the DES algorithm to increase the size of the key controversies First, there were complaints about the key, only as well as expanding and creating robust S- boxes before the 56-bit key length was too short to perform the exhaustive ES-DES algorithm to complete the process using an Enhanced search attack key well-funded opponents[5]. Second, while Secure DES (ES-DES) algorithm.While extending S-Boxes details of the algorithm were published, it was revealed that and increasing the key size, the security of the ES-DES some of the design criteria, which leads to the assumption that algorithm is improved against cryptanalytic attacks as well as the DES contains a hidden security weakness or loophole. In the user maintain the different services (i.e., confidentiality, 1993, Wiener showed an efficient design for a machine message integrity, and authentication) and confusion is costing 1 million. Rec. The United States, which can recover a approximately doubled compared with a DES algorithm. DES key in 3.5 hours[6], which makes it likely that the US government could recover a DES key by exhaustive search in the 1970s. In 1989 godu Biham and Shamir[7] represented In ES-DES Encryption and Decryption DES attack in 1989, using a method called differential The ES-DES is a symmetric block cipher algorithm, the cryptanalysis; In response, IBM stated that the attack was length of the plaintext and key size is 128-bit (i.e., ES-DES known to DES designers, and facilitated the protection of this algorithm, which receives 128-bit blocks of plaintext and 128- technique based on the design criteria for the S-box. bit key(112-bit) as the input to operate successive operation). In 1994 one of the developers DES Boilermaker listed the Being symmetric, the same key and same algorithm are used eight criteria for the design of S-boxes[8], and these criteria for both encryption as well as decryption time, and ES-DES were used to create the original eight DES S-boxes. This also uses the same key, and the same algorithm is used for seems to solve the problem of hospitals. Despite this, NSA's both encryption as well as decryption time but was used in role in DES design and, in particular, are not quite clear S- reverse order. boxes, as public statements by IBM and the NSA on this issue seem inconsistent. Introduction about S-BOX In 1982, Meyer and Mathias, two other members of the DES project team at IBM, discussed the implementation of the S- An S-Box is a substitution technique for convert of R input boxes, and more precisely, the number of minterms needed for bits to S output bits, where R is needed not be essentially their implementation. They argue that the early development equal to S as shown in the following Fig. 2. Each output bit of of the production of S-Boxes with several minternm between S corresponds to the output of a Boolean function of the R 11366 International Journal of Applied Engineering Research ISSN 0973-4562 Volume 12, Number 21 (2017) pp.11365-11373 © Research India Publications.
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