Hill Cipher - 2661 Words

CioheWednesday, April 13, 2016 University of Botswana ISS 334 LAB 2 ASSIGNMENT Ndlovu.I 200902852 Ndlovu.I ISS 334 Lab 2 Assignment Page 1 of 27 Wednesday, April 13, 2016 Contents 1. Hill Cipher Description .......................................................................................................................... 3 2. Question ................................................................................................................................................ 3 3. Implementation .................................................................................................................................... 3 3.1. Hill Cipher Encryption and†¦show more content†¦Step 3 is the same as Step 2 but using a different matrix multiplication to find the key. All the programs have written in java using Dr. Java. Ndlovu.I ISS 334 Lab 2 Assignment Page 3 of 27 Wednesday, April 13, 2016 3.1. Hill Cipher Encryption and Decryption Ndlovu.I ISS 334 Lab 2 Assignment Page 4 of 27 Wednesday, April 13, 2016 3.1.1. Part 1 Class Basic the class has the indexOfChar and indexAtChar method. The first method matches characters of a string to the alphabet and returns a numeric value, the second method is used to return a char which is located at the position int pos. Class Hill has an object basic of the class basic so as to access the methods from the basic class, this is done later on in the program. Class Hill also contains method Hill, this ensures that the matrix we are using is a 2X2 matrix, that’s why the variable block=2. The method reads the key matrix. The user will enter in the first number and press â€Å"enter† and do this until the fourth number is entered. The assumption is that we are using a 2x2 matrix as the key size. Ndlovu.I ISS 334 Lab 2 Assignment Page 5 of 27 Wednesday, April 13, 2016 Ndlovu.I ISS 334 Lab 2 Assignment Page 6 of 27 Wednesday, April 13, 2016 3.1.2. Part 2 The method KeyInverse also reads 4 integers which are stored to the double array Key[][] and uses them for the decryption key. The method encryptBlock isShow MoreRelatedSystematic Study Of Avalanche Effect2978 Words   |  12 Pagessuch algorithm to provide data security. It is further modified as Triple DES (3DES) to provide added security due to the extra key length. In DES, 3DES the data is coded in binary system. Avalanche effect is the variation that is observed in the cipher text due to one bit variation in the plain text. In this paper we implement Triple DES algorithms in which the plain text is encoded using various binary coded decimal systems such as 8421, 7421, 5421, excess-3, gray code etc†¦before encrypting itRead MoreTypes Of Passive And Active Security Attacks Essay2288 Words   |  10 Pagesa What are the two basic functions used in encryption algorithms? (1 points) The functions used in encryption alogirthms are the substitution and transformation of a plaintext to ciphertext. 2.b What are the two general approaches to attacking a cipher? (1 points) The two general approach are: Cryptanalysis Brute-force attack. â€Æ' 2.c List and briefly define types of cryptanalytic attacks based on what is known to the attacker. 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