International Journal of Recent Technology and Engineering (IJRTE) ISSN: 2277-3878, Volume-8, Issue-2S3, July 2019 Research on Various Cryptography Techniques Yahia Alemami, Mohamad Afendee Mohamed, Saleh Atiewi ABSTRACT--- Security plays a critical position in preserving information privacy and secrecy. Many encryption strategies are available to protect data during transmission or storage. These encryption methods vary in terms of strength, speed, and resource consumption (CPU usage, memory, and power). This study aims to present the most popular and interesting algorithms currently in use. Fig. 2: Asymmetric cryptosystem Index Terms — Cryptography, data security, public key, resource consumption, secret key. A. Common Terms Used in Cryptography I. INTRODUCTION Plaintext: The original and understandable text. As an instance, 'Y' needs to transmit a “Computer” message Security is an important in protecting data against to 'Z'. Here, “Computer” is the plaintext or the original intruders. One of the most important methods for ensuring message. data secrecy is cryptography. Cryptography is secret writing Ciphertext: The text that cannot be understood by way for data security protection. Well-hidden data cannot of anybody or a gibberish text, example “A@$&J9.” easily be read, modified or fabricated [1]. Cryptography Encryption: A process of changing clear text into protects crucial data via changing it into unclear data that unclear text. The manner of encipherment needs an can only be accessed via authorized receivers, who then encipherment algorithm and a key. Encipherment converts the uncertain data into the original textual content. occurs on the sender side. The process of changing original text into unclear text Decryption: A reverse method of encode. It is a (ciphertext) with a certain key referred to as encryption, and manner of converting ciphertext into plaintext. the opposite of encryption process is referred to as Key: A key is character, number, or a special decryption process. character. It is used at the time of encipherment on the Privacy and security management present challenges to e- original text and at the time of decode on the exam. An e-exam database requires security and reliability. ciphertext. Thus, an e-exam user’s identity must be established. Computerized exams are prone to significant problems such B. Purpose of Cryptography as leaks, attackers and so on. One solution is to encrypt the Authentication: The potential of a system to test the questions inside the database. Encryption is the conversion identity of the sender. of plaintext to text that is not clear. Confidentiality: Information transmitted ought to be The two fundamental techniques for encrypting data are accessed handiest by using legal parties and not “symmetric cryptography,” which entails the usage of the through anyone else. same key to encrypt/ decode information; and “asymmetric Integrity: Only the authorized parties are permitted to cryptography,” which makes use of public and private keys alter on transmitted information. to encrypt/ decode information. Non-repudiation: Is the guarantee that someone Examples of symmetric algorithms are Data Encryption cannot deny the validity of something. Standard (DES), Triple-DES (3DES), Blowfish, and Advanced Encryption Standard (AES). The most well- Access Control: Just the authorized persons are known asymmetric algorithms are RSA and ELGAMAL capable to get right of entry to the given information. Schema. C. Evaluation Parameters Each encryption algorithm presents strengths and weaknesses in terms of their parameters. Some parameters that determine encryption performance are described as follows. 1) Encryption time: Measured in milliseconds, depend on Fig. 1. Symmetric cryptosystem the data block length and key length. It directly influences the performance of the encryption algorithm. The performance of an algorithm is regarded as advanced when the encryption time is rapid. Revised Manuscript Received on July 10, 2019. Yahia Alemami, Faculty of Informatics and Computing, Universiti Sultan Zainal Abidin, Terengganu, Malaysia. Mohamad Afendee Mohamed, Faculty of Informatics and Computing, Universiti Sultan Zainal Abidin, Terengganu, Malaysia. Saleh Atiewi, Computer Science, Al Hussein Bin Talal University College of IT, Ma’an, Jordan. Published By: Retrieval Number: B10690782S319/19©BEIESP Blue Eyes Intelligence Engineering DOI : 10.35940/ijrte.B1069.0782S319 395 & Sciences Publication RESEARCH ON VARIOUS CRYPTOGRAPHY TECHNIQUES 2) Decryption time: The time period to regain the follows: The 8-bit input to fK is divided into left and original text from ciphertext; it is also measured in right inputs, each of which contains 4 bits for use in milliseconds. The performance of an algorithm is the following equation: fK(L, R) = (L (XOR) F(R, regarded as superior when the decryption time is SK), R) where SK is a subkey and XOR is the bit-by- rapid. bit exclusive-OR function. The initial process is an 3) Memory used: A low memory usage is desirable expansion/permutation process. because it affects system cost. 4) Throughput: Is computed through way of dividing the whole encoded block size on the entire encode time. The fundamental 4 bits are fed inside the S-box S0 to The power consumption of the algorithm will supply a 2-bit outcome, and the residual 4 bits are fed inside decrease, if the throughput cost increases [2]. S1 to provide another 2-bit outcome. These boxes are described as follows: II. ENCRYPTION ALGORITHMS This part clarifies numerous encryption algorithms to identify the best encryption schemes on the basis of various parameters. A. Simplified Data Encryption Standard (S-DES) The steps of the S-DES algorithm described as follows: The S-boxes work as follows: The result of preceding 1) S-DES Key Generation: S-DES relies upon on the steps indicates that the 1st and 4th enter bits are taken into using of a shared key that consist of 10- bit and share consideration a two-bit number that specifies a row of the S- it among both sender and receiver. Pair of 8-bit sub box, and the 2nd and 3rd input bits determine a column of the keys are generated (K1, K2) from this key for use in S-box. S0 is used by the left nibble, and S1 is used by the specific stages of encipherment and decipherment right nibble. The following 4 bits generated through S0 and algorithms as presented in Fig. 3 [3]. S1 undergo further permutation as follows: Both Fig. 4 and 5 illustrate the S-DES. Fig. 3: Key generation for S-DES [3] Both keys are coming through using the functions P10, Shift and P8 where P10 and P8 are as follows: 2) Initial and Final Permutations: The input to the Fig. 4: S-DES scheme [4] algorithm is an eight-bit block of original text, which is initially permuted using the IP function with IP given as follows: At the end of the algorithm, the inverse permutation, IP−1 is applied; here, IP−1 is given as follows: 3) Function fK: This function can be explained as Published By: Retrieval Number: B10690782S319/19©BEIESP Blue Eyes Intelligence Engineering DOI : 10.35940/ijrte.B1069.0782S319 396 & Sciences Publication International Journal of Recent Technology and Engineering (IJRTE) ISSN: 2277-3878, Volume-8, Issue-2S3, July 2019 Fig. 6: Blowfish encryption algorithm [2] Fig. 5: S-DES encryption detail [4] E. Advanced Encryption Standard (AES) B. DES AES was deployment by the National Institute of Standards and Technology in 2001; it is also called DES is the earliest symmetric encipherment algorithm “Rijndael” [5]. introduced in 1972 by International Business Machines AES is a block cipher with a block size of 128 bits. The Corporation and in 1977 it has been Agreed as Federal key length can be 128, 192 or 256 bits. Encipherment Information Processing Standard through the National includes ten rounds of processing for 128-bit keys, 12 Bureau of Standard [2]. It comprises the same steps as S- rounds for 192-bit keys and 14 rounds for 256-bit keys. The DES and processes a 64-bit input with a preliminary algorithm is called AES-128, AES-192 or AES-256 relying permutation. In DES, the number of rounds is 16 while in S- on the key size [5]. The steps for every round include of 4 DES is two rounds also the S-DES uses 8 bits for input. layers, particularly, replacement byte, shift rows, blend C. Triple DES (3DES) column and add round key as appear in Fig. 7 [2]. 3DES was suggested by IBM (International Business Machines Corporation) in 1998. A substitute for DES, 3DES shows improved key size and applies the DES algorithm 3 rounds in each data block. The key length for the 3DES is 112 and 168 bits, the number of rounds is 48 and the block length is 64 bits [2]. This algorithm aims to increase protection and security through its longer key size relative to DES. However, it is more time consuming than DES is when applied to the encryption process. D. Blowfish Blowfish is a type of symmetric block cipher generated by B. Schneier in 1993. Blowfish is fast algorithm, license free, and unpatented. It uses a key length in the range of 32– 448 and a sixty-four-bit block. The Blowfish algorithm makes use 16 round for the encipherment procedure Fig. 6. Blowfish ordinarily makes use of 4 S-boxes rather than of one S-box. It requires additional processing time because it relies on key length, however it provides strong safety [2]. Fig. 7: AES algorithm [2] Published By: Retrieval Number: B10690782S319/19©BEIESP Blue Eyes Intelligence Engineering DOI : 10.35940/ijrte.B1069.0782S319 397 & Sciences Publication RESEARCH ON VARIOUS CRYPTOGRAPHY TECHNIQUES III. LITERATURE REVIEW & RESULTS The Diffie–Hellman protocol has been applied to many A secure socket layer (SSL) channel guarantees that all security protocols including SSL, secure shell and IP information passed between the web server and the browser security [13].