Abstracts Computer Science

HYPERCHAOTIC PIXEL SHUFFLE BASED IMAGE CRYPTOSYSTEM

by Krishnendu Rarhi

The problems of confidentiality, authenticity and anonymity have been studied for long in cryptography, and the notion of provable security is the foundation for most, if not all, modern cryptographic research. With great advancements in technology, there is also a need to define and view these concepts of security under various dimensions. One such recent dimension of security is the Cryptanalysis. Cryptanalysis refers to the study of ciphers, ciphertext, or cryptosystems (that is, to secret code systems) with a view to find weaknesses in them that will permit retrieval of the plaintext from the ciphertext, without necessarily knowing the key or the algorithm. In this term paper we propose an efficient ciphertext only method of attacking multi-chaotic image encryption scheme. In this work, we first look at the overview of cryptography in general, where the place and role of cryptography in a communication system is given as well. Secondly, we provide a comprehensive description of why we are using Ciphertext only cryptanalysis on multi-chaotic image encryption schemes. We have also considered the standard definitions and notations that are frequently used in Chaos Theory and Image Cryptosystem. Next we have provided an overview of different cryptanalysis methods in cryptography. Here the focus is on multi-chaotic systems based image cryptosystem, and, more specifically, on correlation and distinguishing attacks when different scenarios are possible. In our next move we look at the proposed course of action on which we will conduct our further work. This thesis Project Progress Report proffers a new ciphertext only attack on multi-chaotic image encryption scheme a different outlook.