Musheer Ahmad

Musheer Ahmad, Akshay Chopra

In this paper, we propose an image encryption algorithm based on the chaos, substitution boxes, nonlinear transformation in Galois field and Latin square. Initially, the dynamic S boxes are generated using Fisher Yates shuffle method and piece wise linear chaotic map. The algorithm utilizes advantages of keyed Latin square and transformation to substitute highly correlated digital images and yield encrypted image with valued performance. The chaotic behavior is achieved using Logistic map which is used to select one of thousand S boxes and also decides the row and column of selected S box. The selected S box value is transformed using nonlinear transformation. Along with the keyed Latin square generated using a 256 bit external key, used to substitute secretly plain image pixels in cipher block chaining mode. To further strengthen the security of algorithm, round operation are applied to obtain final ciphered image. The experimental results are performed to evaluate algorithm and the anticipated algorithm is compared with a recent encryption scheme. The analyses demonstrate algorithms effectiveness in providing high security to digital media.

Musheer Ahmad, Nikhil Mittal, Prerit Garg et al.

Symmetric encryption has been a standout amongst the most reliable option by which security is accomplished. In modern block symmetric ciphers, the substitution-boxes have been playing a critical role of nonlinear components that drives the actual security of ciphers. In this paper, the travelling salesman problem and piecewise linear chaotic map are explored to synthesize an efficient configuration of 8x8 substitution-box. The proposed anticipated design has the consistency which is justified by the standard performance indexes. The statistical results manifest that the prospective substitution-box is cryptographically more impressive as compared to some recent investigations.

Musheer Ahmad, Hamed D AlSharari

Substitution boxes with thorough cryptographic strengths are essential for the development of strong encryption systems. They are the only portions capable of inducing nonlinearity in symmetric encryption systems. Bijective substitution boxes having both high nonlinearities and high algebraic complexities are the most desirable to thwart linear, differential and algebraic attacks. In this paper, a method of constructing algebraically complex and cryptographically potent multiple substitution boxes is proposed. The multiple substitution boxes are synthesized by applying the concept of rotation-k approach on the affine-power-affine structure. It is shown that the rotation-k approach inherits all the features of affine-power-affine structure. Performance assessment of all the proposed substitution boxes is done against nonlinearity, strict avalanche criteria, bits independent criteria, differential probability, linear approximation probability and algebraic complexity. It has been found that the proposed substitution boxes have outstanding cryptographic characteristics and outperform the various recent substitution boxes.

Swaleha Saeed, M Sarosh Umar, M Athar Ali et al.

In Present era, information security is of utmost concern and encryption is one of the alternatives to ensure security. Chaos based cryptography has brought a secure and efficient way to meet the challenges of secure multimedia transmission over the networks. In this paper, we have proposed a secure Grayscale image encryption methodology in wavelet domain. The proposed algorithm performs shuffling followed by encryption using states of chaotic map in a secure manner. Firstly, the image is transformed from spatial domain to wavelet domain by the Haar wavelet. Subsequently, Fisher Yates chaotic shuffling technique is employed to shuffle the image in wavelet domain to confuse the relationship between plain image and cipher image. A key dependent piece-wise linear chaotic map is used to generate chaos for the chaotic shuffling. Further, the resultant shuffled approximate coefficients are chaotically modulated. To enhance the statistical characteristics from cryptographic point of view, the shuffled image is self keyed diffused and mixing operation is carried out using keystream extracted from one-dimensional chaotic map and the plain-image. The proposed algorithm is tested over some standard image dataset. The results of several experimental, statistical and sensitivity analyses proved that the algorithm provides an efficient and secure method to achieve trusted gray scale image encryption.

Parvez Mahmood Khan, M M Sufyan Beg, Musheer Ahmad

Growth in the number of PMOs established by the industry over last decade and ever growing body of literature on PMO related research in academia is a clear indication that there is very clear interest of researchers, practitioners and industries across the globe to understand and explore value propositions of PMO. However, there is still a lack of consensus on many critical aspects of PMOs. While there are many PMOs being established, but there are also many being closed and disbanded, which is definitely a matter of concern. In industry environment, a narrow majority of PMOs are well-regarded by their organizations and are seen as contributing business value, many of the others are still struggling to show value for money and some are failing, causing a high mortality rate among PMOs. This paper is the result of a study undertaken to get a deeper understanding of factors that may be causing mortality and failure of PMOs. Post Implementation Reviews of 4-failed & 3-challenged PMOs in IT-Industry were carried out with concerned Project Managers & PMO-staff, using grounded theory research method, with support from the concerned enterprise from IT-Industry.

Musheer Ahmad, Hamed D. Alsharari, Munazza Nizam

In this paper, we propose to improve the security performance of a recently proposed color image encryption algorithm which is based on multi-chaotic systems. The existing cryptosystem employed a pixel-chaotic-shuffle mechanism to encrypt images, in which the generation of shuffling sequences are independent to the plain-image/cipher-image. As a result, it fails to the chosen-plaintext and known-plaintext attacks. Moreover, the statistical features of the cryptosystem are not up to the standard. Therefore, the security improvements are framed to make the above attacks infeasible and enhance the statistical features as well. It is achieved by modifying the pixel-chaotic-shuffle mechanism and adding a new pixel-chaotic-diffusion mechanism to it. The keys for diffusion of pixels are extracted from the same chaotic sequences generated in the previous stage. The simulation analyses and studies are performed to demonstrate that the updated version of cryptosystem has better statistical features and resistant to the chosen-plaintext and known-plaintext attacks than the existing algorithm.

Musheer Ahmad, Bashir Alam, Omar Farooq

In this paper, a high dimensional chaotic systems based mixed keystream generator is proposed to secure the voice data. As the voice-based communication becomes extensively vital in the application areas of military, voice over IP, voice-conferencing, phone banking, news telecasting etc. It greatly demands to preserve sensitive voice signals from the unauthorized listening and illegal usage over shared/open networks. To address the need, the designed keystream generator employed to work as a symmetric encryption technique to protect voice bitstreams over insecure transmission channel. The generator utilizes the features of high dimensional chaos like Lorenz and Chen systems to generate highly unpredictable and random-like sequences. The encryption keystream is dynamically extracted from the pre-treated chaotic mixed sequences, which are then applied to mask the voice bitstream for integrity protection of voice data. The experimental analyses like auto-correlation, signal distribution, parameter residual deviation, key space and key-sensitivity demonstrate the effectiveness of the proposed technique for secure voice communication.

Musheer Ahmad, Hamed D Al-Sharari

In this paper, a simple and robust color image encryption algorithm based on high-dimensional chaotic maps is proposed. The algorithm employs a 3D Arnold transform to perform inter-component shuffling of plain-image, while a 2D hyper-chaotic map is used to confuse the relationship between the encrypted image and plain-image. The control parameters of Arnold transform are extracted from pending plain-image, thereby establishing a dependency to the plain-image. The confusion process is carried out in cipher-block chaining mode to make it dependent to the encrypted image. This makes the algorithm able to resist the cryptographic attacks. The performance of the proposed algorithm is analyzed through computer simulations. The experimental analyses show that the proposed algorithm has desirable properties of high security, robustness to cryptographic attacks and practicability to protect multimedia color images.