RDA Algortihm: Symmetric Key Algorithm
|Author(s)||Dinesh Goyal,Vishal Srivastava|
|Issue Date||April, 2012|
|Publishing Date||April, 2012|
|Keywords||RDA Algorithm, symmetric key|
Cryptography is an art of illusion in which the sender encodes the message using a key and sends it over the communication channel. The receiver on the other side of the channel decodes the message back and using the key tries to obtain back the original message. If the key during the communication is same on both sides then it is called as symmetric key cryptography and if is called as asymmetric key cryptography. There has been different encoding techniques used for the pain text in both block & stream cipher mode some of them are ECB & CBC for block cipher & OFB & CBC for block cipher.
Vigenere Cipher is a Caesar Cipher substitution technique where in a Caesar cipher, each letter of the alphabet is shifted along some number of places; for example, in a Caesar cipher of shift 3, A would become D,B would become E and so on . The Vigenere cipher consists of several Caesar ciphers in sequence with different shift values. To encipher, a table of alphabets can be used, termed a Vigenere square, or Vigenere table. It consists of the alphabet written out 26 times in different rows, each alphabet shifted cyclically to the left compared to the previous alphabet, corresponding to the 26 possible Caesar ciphers. At different points in the encryption process, the cipher uses a different alphabet from one of the rows. The alphabet used at each point depends on a repeating keyword. Decryption is performed by finding the position of the cipher text letter in a row of the table, and then taking the label of the column in which it appears as the plaintext. For example, in row L, the cipher text .L appears in column A, which taken as the first plaintext letter. The second letter is decrypted by looking up x in row E of the table; it appears in column T, which is taken as the plaintext letter.
In this paper an attempt is made to design a new model of Symmetric key Cryptography using Vigenere Cipher Technique and ECB Encoding.