A Robust Encryption Technique Using Enhanced Vigenre Cipher

Document Type : Research Paper


1 Computer Science Department, College of Science, University of Diyala, Diyala, Iraq

2 Supervision and Scientific Education Apparatus, International Accreditation Department, Ministry of Higher Education, Iraq



A lot of data in this world are very important and no matter how simple it can be. Hence the number
of data conveyed through the internet still increasing due to the rapid development of computer
technology. In order to save the data over the internet, cryptography is a technique for conveying
information securely between two parties without interference from outside elements. The Vigenre
cipher is a technique of encrypting alphabetic text via using a sequence of different Caesar ciphers
depend on the letters of a keyword. It is a simple form of polyalphabetic replacement. In this paper,
the traditional way for the Vigenre method is enhanced by using two keys for text encryption. The
first key is used to format the table of the alphabet (26 characters) and second keys are used to
encrypt the plain text like the original Vigenre cipher. The result shows the proposed method is
efficient and stronger against the kasiski and Friedman attack to find the length of the key.