Papers by Narendra Pareek
International Journal of Advanced Research and Development, 2018
Journal of Applied Nonlinear Dynamics, 2018
A novel quasigroup substitution scheme for chaos based image encryption During last two decades, ... more A novel quasigroup substitution scheme for chaos based image encryption During last two decades, there has been a prolific growth in the chaos based image encryption algorithms. Up to an extent these algorithms have been able to provide an alternative to exchange large media files (images and videos) over the networks in a secure way. However, there have been some issues with the implementation of chaos based image ciphers in practice. One of them is reduced/small key space due to the fact that chaotic behavior is only observed for certain range of system parameters/initial conditions of the chaotic system used in such algorithms. To overcome this difficulty, we propose a simple, efficient and robust image encryption algorithm based on combined applications of quasigroups and chaotic standard map. The proposed image cipher is based on the Shannon's popular substitution-diffusion architecture where a quasigroup of order 256 and chaotic standard map have been used for the substitution and permutation of image pixels respectively. Due to the introduction of quasigroup as part of the secret key along with the parameter and initial conditions of the chaotic standard map, the key space has been increased significantly. The proposed image cipher is very fast due to the fact that the substitution based on the quasigroup operations is very simple and can be executed easily through the lookup table operations on Latin squares (which are Cayley operation tables of quasigroups) and the permutation is performed row-by-row as well as column-by-column using the pseudo random number sequences generated through the chaotic standard map. The security and performance have been analyzed through the histograms, correlation coefficients, information entropy, key sensitivity analysis, differential analysis, key space analysis etc. and the results prove the efficiency and robustness of the proposed image cipher against the possible security threats.
Journal of Information Science, 2014
Pseudo relevance feedback-based query expansion is a popular automatic query expansion technique.... more Pseudo relevance feedback-based query expansion is a popular automatic query expansion technique. However, a survey of work done in the area shows that it has a mixed chance of success. This paper captures the limitations of pseudo relevance feedback (PRF)-based query expansion and proposes a method of enhancing its performance by hybridizing corpus-based information, with a genetic fuzzy approach and semantic similarity notion. First the paper suggests use of a genetic fuzzy approach to select an optimal combination of query terms from a pool of terms obtained using PRF-based query expansion. The query terms obtained are further ranked on the basis of semantic similarity with original query terms. The experiments were performed on CISI collection, a benchmark dataset for information retrieval. It was found that the results were better in both terms of recall and precision. The main observation is that the hybridization of various techniques of query expansion in an intelligent way ...
Information and Communication Technology for Intelligent Systems (ICTIS 2017) - Volume 2, 2017
This paper presents a comparative analysis of Digital Cosine Transformation (DCT) technique and D... more This paper presents a comparative analysis of Digital Cosine Transformation (DCT) technique and Discrete Wavelet Transformation (DWT) technique in digital image watermarking. We have used standard digital images for analysing of Watermarked Images and applied standard attacks on the watermarked image. An experimental comparison was made using Matlab.
The idea to connect everything to anything and at any point of time is what vaguely defines the c... more The idea to connect everything to anything and at any point of time is what vaguely defines the concept of the Internet of Things (IoT). The IoT is not only about providing connectivity but also facilitating interaction among these connected things. Though the term IoT was introduced in 1999 but has drawn significant attention during the past few years, the pace at which new devices are being integrated into the system will profoundly impact the world in a good way but also poses some severe queries about security and privacy. IoT in its current form is susceptible to a multitudinous set of attacks. One of the most significant concerns of IoT is to provide security assurance for the data exchange because data is vulnerable to some attacks by the attackers at each layer of IoT. The IoT has a layered structure where each layer provides a service. The security needs vary from layer to layer as each layer serves a different purpose. This paper aims to analyze the various security and privacy threats related to IoT. Some attacks have been discussed along with some existing and proposed countermeasures.
Communications in Nonlinear Science and Numerical Simulation, 2010
Recently Patidar et al. [Commun Nonlinear Sci Numer Simulat 14;2009:3056-75] proposed a new subst... more Recently Patidar et al. [Commun Nonlinear Sci Numer Simulat 14;2009:3056-75] proposed a new substitution-diffusion image cipher using chaotic standard and logistic maps, which is very fast and possess all the confusion and diffusion properties that any good cryptosystem should have. Soon after the proposal, Rhouma et al. [Commun Nonlinear Sci Numer Simulat 2010;15:1887-92.] proposed an equivalent description of the PPS09 cryptosystem which facilitated them in the cryptanalysis of the original cipher in terms of chosen plainext and known plaintext attacks. In this paper, we propose modifications in the Patidar et al.'s image cipher to make it robust against these two cryptanalytic attacks. The security analysis shows that the modified image cipher preserves all the good properties of the original cipher and is also capable to stand against the aforesaid attacks.
Communications in Nonlinear Science and Numerical Simulation, 2009
... Cited By in Scopus (12). Permissions & Reprints. A new substitutiondiffusion bas... more ... Cited By in Scopus (12). Permissions & Reprints. A new substitutiondiffusion based image cipher using chaotic standard and logistic maps. Vinod Patidar a , Corresponding Author Contact Information , E-mail The Corresponding Author , NK Pareek b and KK Sud a. ...
In this paper, a new image encryption scheme using a secret key of 144-bits
Chaotic systems have many interesting features such as sensitivity on initial condition and syste... more Chaotic systems have many interesting features such as sensitivity on initial condition and system parameter, ergodicity and mixing properties. In this paper, we exploit these interesting properties of chaotic systems to design a random bit generator, called CCCBG, in which two chaotic systems are cross-coupled with each other. To evaluate the randomness of the bit streams generated by the CCCBG, the four basic tests: monobit test, serial test, auto-correlation, Poker test and the most stringent tests of randomness: the NIST suite tests have been performed. As a result no patterns have been observed in the bit streams generated by the proposed CCCBG. The proposed CCCBG can be used in many applications requiring random binary sequences and also in the design of secure cryptosystems.
Use of rule sets of popular games, especially in design of image encryption algorithm, leads to a... more Use of rule sets of popular games, especially in design of image encryption algorithm, leads to a new paradigm in the field of cryptography. The paper aims to study a newly designed digital grey image encryption scheme that uses knight moving rules (game of chess) in conjunction with an external secret key of 128-bits size. In the propose scheme, image is divided into several squared sub-images and knight tour is used to scramble the pixels of sub-image. The starting position of knight on a board (sub-image) as well as pixel substitution depends on the secret key used in the algorithm. The propose encryption scheme has total fifteen rounds and each round has four different processes. Performance analysis shows that the proposed scheme has good statistical character, key sensitivity and can resist attack efficiently. Keywords— Knight tour, Grey image encryption, Secret key, Image cipher, Pixel scrambling, Image security.
Informatica (Slovenia), 2009
During last one and half decade an interesting relationship between chaos and cryptography has be... more During last one and half decade an interesting relationship between chaos and cryptography has been developed, according to which many properties of chaotic systems such as: ergodicity, sensitivity to initial conditions/system parameters, mixing property, deterministic dynamics and structural complexity can be considered analogous to the confusion, diffusion with small change in plaintext/secret key, diffusion with a small change within one block of the plaintext, deterministic pseudo randomness and algorithmic complexity properties of traditional cryptosystems. As a result of this close relationship several chaos-based cryptosystems have been put forward since 1990. In one of the stages of the development of chaotic stream ciphers, the application of discrete chaotic dynamical systems in pseudo random bit generation has been widely studied recently. In this communication, we propose a novel pseudo random bit generator (PRBG) based on two chaotic logistic maps running side-by-side a...
Internet communication has become an integral part of the infrastructure of todays world. In rece... more Internet communication has become an integral part of the infrastructure of todays world. In recent years, owing to frequent flow of information and digital images across the world over the transmission media, it has become essential to secure them from leakages. Many applications like telephonic messages, email, banking, trade, e-commerce etc., require reliable, fast and robust security system to store and transmit information and digital images. Currently, number of popular security tools like stegnanography, digital watermarking, cryptography etc are available but among them cryptography has taken prominent place in security. Recently, researchers from the nonlinear dynamics community have noticed an interesting relationship between chaos and cryptography. Chaotic systems have properties like ergodicity, sensitivity to initial conditions/system parameters, mixing property, deterministic dynamics and structural complexity. They have attracted attention of cryptographers to develop...
In this paper, a new image encryption scheme for colour BMP images using a secret key of 120-bits... more In this paper, a new image encryption scheme for colour BMP images using a secret key of 120-bits is proposed. Initially, image is divided into blocks subsequently into color components. Each color component is modified by performing bitwise operation which depends on secret key used in algorithm as well as a few most significant bits of its previous and next color component. Three rounds are taken to complete this process. To make cipher more robust, a feedback mechanism is applied by modifying the used secret key after encrypting each block. The propose scheme is simple, fast and sensitive to the secret key. Due to high order of substitution, common attacks like linear and differential cryptanalysis are infeasible. The experimental results show that the proposed encryption technique is efficient and has high security features.
This paper is focused towards query expansion, which is an important technique for improving retr... more This paper is focused towards query expansion, which is an important technique for improving retrieval efficiency of an Information Retrieval System. Specifically the paper proposes a novel evolutionary approach for improving efficiency of Pseudo Relevance Feedback (PRF) Based Query Expansion. In this method the candidate terms for query expansion are selected from an initially retrieved list of documents, ranked on the basis of co-occurrence measure of the terms with the query terms. Top n selected terms create a term pool. From this term pool, Genetic Algorithm is used to select a thematically rich combination of terms, which provide the terms for expanding the query. We call this method as Genetic Algorithm Based Query Expansion (GABQE). The experiments were performed on standard CISI dataset. The results are quite motivating and one can clearly observe the difference in the result when GA is not used and when GA is used. The paper uses GA for improving PRF based query expansion,...
This paper introduces a grey wolf optimization algorithm for image watermarking in the Wavelet Tr... more This paper introduces a grey wolf optimization algorithm for image watermarking in the Wavelet Transform domain. Digital image watermarking (DIW) determine its proficiency in ensuring illegal confirmation of media. The visibility factor of the watermark is the main parameter that helps in enhancing the robustness, and perceptual transparency of the DIW. The trade-off between the clarity and robustness is considered as an optimization problem and is explained by applying GWO algorithm. The effectiveness of proposed scheme is evaluated in terms of PSNR, and MSE. The simulation results are carried out using MATLAB R2014b software.
International Journal of Network Security & Its Applications, 2012
In this paper, a new image encryption scheme using a secret key of 144-bits is proposed. In the s... more In this paper, a new image encryption scheme using a secret key of 144-bits is proposed. In the substitution process of the scheme, image is divided into blocks and subsequently into color components. Each color component is modified by performing bitwise operation which depends on secret key as well as a few most significant bits of its previous and next color component. Three rounds are taken to complete substitution process. To make cipher more robust, a feedback mechanism is also applied by modifying used secret key after encrypting each block. Further, resultant image is partitioned into several key based dynamic sub-images. Each sub-image passes through the scrambling process where pixels of sub-image are reshuffled within itself by using a generated magic square matrix. Five rounds are taken for scrambling process. The propose scheme is simple, fast and sensitive to the secret key. Due to high order of substitution and permutation, common attacks like linear and differential cryptanalysis are infeasible. The experimental results show that the proposed encryption technique is efficient and has high security features.
International Journal of Applied Research on Information Technology and Computing, 2014
The security of digital medical images attracts much attention recently, especially when these im... more The security of digital medical images attracts much attention recently, especially when these images are sent through the communication networks. An image encryption technique converts an image to another image that is hard to understand. In the proposed method, bitwise operations are exploited to develop a new and fast grey scale medical image encryption algorithm. Theoretical and experimental analyses both confirm the security and the validity of the proposed algorithm.
Recently, Pareek et al. (Phys. Lett. A 309 (2003) 75) have developed a symmetric key block cipher... more Recently, Pareek et al. (Phys. Lett. A 309 (2003) 75) have developed a symmetric key block cipher algorithm using a one-dimensional chaotic map. In this paper, we propose a symmetric key block cipher algorithm in which multiple one-dimensional chaotic maps are used instead of a one-dimensional chaotic map. However, we also use an external secret key of variable length (maximum 128-bits) as used by Pareek et al. In the present cryptosystem, plaintext is divided into groups of variable length (i.e. number of blocks in each group is different) and these are encrypted sequentially by using randomly chosen chaotic map from a set of chaotic maps. For block-by-block encryption of variable length group, number of iterations and initial condition for the chaotic maps depend on the randomly chosen session key and encryption of previous block of plaintext, respectively. The whole process of encryption/decryption is governed by two dynamic tables, which are updated time to time during the encry...
Internet communication has become an integral part of the infrastructure of today’s world. In rec... more Internet communication has become an integral part of the infrastructure of today’s world. In recent years, owing to frequent flow of information and digital images across the world over the transmission media, it has become essential to secure them from leakages. Many applications like telephonic messages, email, banking, trade, e-commerce etc., require reliable, fast and robust security system to store and transmit information and digital images. Currently, number of popular security tools like stegnanography, digital watermarking, cryptography etc are available but among them cryptography has taken prominent place in security. Recently, researchers from the nonlinear dynamics community have noticed an interesting relationship between chaos and cryptography. Chaotic systems have properties like ergodicity, sensitivity to initial conditions/system parameters, mixing property, deterministic dynamics and structural complexity. They have attracted attention of cryptographers to develo...
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Papers by Narendra Pareek