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Kashyap R.,Lal Bahadur Shastri Institute of Management | Vidyarthi D.P.,Jawaharlal Nehru University
Proceedings - 17th IEEE International Conference on Computational Science and Engineering, CSE 2014, Jointly with 13th IEEE International Conference on Ubiquitous Computing and Communications, IUCC 2014, 13th International Symposium on Pervasive Systems, Algorithms, and Networks, I-SPAN 2014 and 8th International Conference on Frontier of Computer Science and Technology, FCST 2014 | Year: 2015

Virtualization is critical to cloud computing because it simplifies the delivery of services by providing a platform for optimizing complex IT resources in a scalable manner. Virtualization architecture provides this illusion through hypervisors/Virtual Machine Monitor, which maps the physical resource to Virtual machines. Security is very essential for cloud users as they relinquish physical possession of their computation and data, which inevitably poses new security risks towards the confidentiality and integrity of the data. Lot of research is initiated in resource provisioning for hypervisors, but still many problems need to be addressed specially for security-aware and real time tasks. A dual objective scheduling algorithm, Real Time Security Maximization (RT-Smax), which aims to meet the deadline of the Virtual machines with best possible security is being proposed. Though this algorithm can be used by any hypervisor, for the current work it has been implemented on Xen VMM. Finally its effectiveness is validated by comparing it with Xen's credit scheduler on security demanding tasks having stringent deadline constraints. © 2014 IEEE.

Jha P.C.,University of Delhi | Bali S.,Lal Bahadur Shastri Institute of Management | Kumar U.D.,Indian Institute of Management | Pham H.,Rutgers University
Memetic Computing | Year: 2014

In developing software systems, a manager's goal is to design software using limited resources and meet the user requirements. One of the important user requirements concerns the reliability of the software. The decision to choose the right software modules (components) becomes extremely difficult because of the number of parameters to be considered while making the decision. If suitable components are not available, then the decision process is further complicated with build versus buy decisions. In this paper, we have formulated a fuzzy multi-objective approach to optimal decision "build-or-buy" for component selection for a fault-tolerant modular software system under the consensus recovery block scheme. A joint optimization model is formulated where the two objectives are maximization of system reliability and minimization of the system cost with a constraint on delivery time. An example of developing a retail system for small-and-medium-size enterprises is used to illustrate the proposed methodology. © 2013 Springer-Verlag Berlin Heidelberg.

Jha P.C.,University of Delhi | Kapur P.K.,University of Delhi | Bali S.,Lal Bahadur Shastri Institute of Management | Kumar U.D.,Indian Institute of Management
International Journal of Reliability, Quality and Safety Engineering | Year: 2010

Computer based systems have increased dramatically in scope, complexity, pervasiveness. Most industries are highly dependent on computers for their basic day to day functioning. Safe & reliable software operations are an essential requirement for many systems across different industries. The number of functions to be included in a software system is decided during the software development. Any software system must be constructed in such a way that execution can resume even after the occurrence of failure with minimal loss of data and time. Such software systems which can continue execution even in presence of faults are called fault tolerant software. When failure occurs one of the redundant software modules get executed and prevent system failure. The fault tolerant software systems are usually developed by integrating COTS (commercial off-the-shelf) software components. The motivation for using COTS components is that they will reduce overall system development costs and reduce development time. In this paper, reliability models for fault tolerant consensus recovery blocks are analyzed. In first optimization model, we formulate joint optimization problem in which reliability maximization of software system and execution time minimization for each function of software system are considered under budgetary constraint. In the second model the issue of compatibility among alternatives available for different modules, is discussed. Numerical illustrations are provided to demonstrate the developed models. © 2010 World Scientific Publishing Company.

Sahi G.,Lal Bahadur Shastri Institute of Management | Madan S.,University of Delhi
Communications in Computer and Information Science | Year: 2013

The current invigorated wave of E-commerce initiatives, post the initial boom and dot com bubble burst is definitely more prudent. Therefore, business community is looking to academe for understanding of how usability can be increased to reap the numerous benefits of E-commerce. This study has been undertaken in context of B2C E-commerce websites and its main purpose is to analyze the differential impact of web usability dimensions on perceived usefulness. This is done by studying customers' responses regarding B2C E-commerce websites with respect to four usability dimensions. A questionnaire survey is used to collect data from select respondents (N=415) and analysis is performed using structural equation modelling (SEM). Findings suggest that although all four dimensions significantly impact perceived usefulness, system quality followed by trust are the two most important factors. The study has important implications for website designers, developers and researchers. © Springer International Publishing Switzerland 2013.

Kashyap R.,Lal Bahadur Shastri Institute of Management | Vidyarthi D.P.,Jawaharlal Nehru University
IAENG International Journal of Computer Science | Year: 2012

The conflict between achieving good performance, in terms of time etc., and achieving high quality of security protection introduces new challenges in security critical grid scheduling. Extensive study indicates that the scheduling performance is affected by the heterogeneities of security and computational power of resources. Different jobs may have varied security requirement and even the same security requirement may exhibit different security overhead on different nodes. This paper proposes a GA based dual objective scheduling algorithm, Dual Objective Security Driven Scheduling using Genetic Algorithm (DO-SDSG). Maximization of security offered to tasks with minimization of security overhead are the two objectives of DO-SDSG. Being a dual objective scheduling problem, it alternatively optimizes the objectives. When one objective is optimized the other one is taken as a constraint and vice-versa. The simulation study demonstrates that the proposed algorithm delivers better makespan, better security with less security overhead in comparison to other such algorithms viz. MinMin, MaxMin, SPMinMin and SPMaxMin.

Rishi M.,Lal Bahadur Shastri Institute of Management | Joshi G.,Lal Bahadur Shastri Institute of Management
Worldwide Hospitality and Tourism Themes | Year: 2016

Purpose – The purpose of this study is to identify the emerging challenges that are faced by branded budget hotels in India. The paper aims to do this by exploring the expectations as well as challenges faced by the customers and hospitality managers of branded budgets hotels in India. Design/methodology/approach – Utilizing a multi-method approach, data were collected through literature review, eight in-depth interviews and 422 customer reviews. Thematic analysis using the hybrid approach brings out the challenges faced by hospitality managers of branded budget hotels in India. Findings – Hospitality managers face the following challenges – dipping gross operating profits, higher global distribution systems productivity for international hotel brands, location constraints, high royalty structures for management contracts, regulatory issues, business poaching and unorganized growth, bureaucracy among vendors and contactors and lack of trained manpower. Customer expectations include poor check-in/check-out services, inefficient service management, inconsiderate personnel, poor management of feedback and instances of theft. Originality/value – This work adds to the body of knowledge using real customer data and thematic analysis. The authors have not come across any scholarly work, especially in the Indian context, which looks at two stakeholders of the branded budget hotel industry. Hence, recommendations from this work are valuable for hospitality managers as well as researchers. © 2016, © Emerald Group Publishing Limited.

Kashyap R.,Lal Bahadur Shastri Institute of Management | Vidyarthi D.P.,Jawaharlal Nehru University
Concurrency Computation Practice and Experience | Year: 2012

Grid applications with stringent security requirements introduce challenging concerns because the schedule devised by nonsecurity-aware scheduling algorithms may suffer in scheduling security constraints tasks. To make security-aware scheduling, estimation and quantification of security overhead is necessary. The proposed model quantifies security, in the form of security levels, on the basis of the negotiated cipher suite between task and the grid-node and incorporates it into existing heuristics MinMin and MaxMin to make it security-aware MinMin(SA) and MaxMin(SA). It also proposes SPMaxMin (Security Prioritized MinMin) and its comparison with three heuristics MinMin(SA), MaxMin(SA), and SPMinMin on heterogeneous grid/task environment. Extensive computer simulation results reveal that the performance of the various heuristics varies with the variation in computational and security heterogeneity. Its analysis over nine heterogeneous grid/task workload situations indicates that an algorithm that performs better for one workload degrades in another. It is conspicuous that for a particular workload one algorithm gives better makespan while another gives better response time. Finally, a security-aware scheduling model is proposed, which adapts itself to the dynamic nature of the grid and picks the best suited algorithm among the four analyzed heuristics on the basis of job characteristics, grid characteristics, and desired performance metric. © 2011 John Wiley & Sons, Ltd.

Jha P.C.,University of Delhi | Bali S.,Lal Bahadur Shastri Institute of Management
Proceedings of the 2012 International Conference on Recent Advances in Computing and Software Systems, RACSS 2012 | Year: 2012

The dependence of mankind on software systems has made it necessary to produce highly reliable software. Software reliability is the major dynamic attribute of the software quality. Hence, it is essential to ensure software reliability for software products. The computer revolution has benefited society and increased the global productivity, but a major threat of this revolution is that the world has become critically dependent on the computing systems for proper functioning and timing of all its activities. While designing software it becomes very important to identify the critical modules in a software system. A system can be made fault tolerant by adding redundant components. Adding redundancy in critical modules may increase the reliability of the system and hence prevents system failure. So this paper aims at optimal selection of COTS components by minimizing the absolute deviational execution time by simultaneously maximizing the system reliability with a constraint on criticality of modules under fuzzy environment. © 2012 IEEE.

Kashyap R.,Lal Bahadur Shastri Institute of Management | Vidyarthi D.P.,Jawaharlal Nehru University
Journal of Grid Computing | Year: 2013

Number of software applications demands various levels of security at the time of scheduling in Computational Grid. Grid may offer these securities but may result in the performance degradation due to overhead in offering the desired security. Scheduling performance in a Grid is affected by the heterogeneities of security and computational power of resources. Customized Genetic Algorithms have been effectively used for solving complex optimization problems (NP Hard) and various heuristics have been suggested for solving Multi-objective optimization problems. In this paper a security driven, elitist non-dominated sorting genetic algorithm, Optimal Security with Optimal Overhead Scheduling (OSO2S), based on NSGA-II, is proposed. The model considers dual objectives of minimizing the security overhead and maximizing the total security achieved. Simulation results exhibit that the proposed algorithm delivers improved makespan and lesser security overhead in comparison to other such algorithms viz. MinMin, MaxMin, SPMinMin, SPMaxMin and SDSG. © 2013 Springer Science+Business Media Dordrecht.

Jha P.C.,University of Delhi | Kaur R.,Institute of Information Technology and Management | Bali S.,Lal Bahadur Shastri Institute of Management | Madan S.,University of Delhi
International Journal of Reliability, Quality and Safety Engineering | Year: 2013

Application Package Software (APS) has emerged as a ready-to-use solution for the software industry. The software system comprises of a number of components which can be either purchased from the vendor in the form of COTS (Commercial Off-the-Shelf) or can be built in-house. Such a decision is known as Build-or-Buy decision. Under the situations wherein the software has the responsibility of supervising life-critical systems, the inception of errors in software due to inadequate or incomplete testing, is not acceptable. Such life-critical systems enforces upon meeting the quality standards of the software as unforbiddenable. This can be achieved by incorporating a fault-tolerant design that enables a system to continue its intended operation rather than failing completely when some part of the system fails. Moreover, while designing a fault-tolerant system, it must be apprehended that 100% fault tolerance can never be achieved and the closer we try to get to 100%, the more costly the system will be. The proposed model shall incorporate consensus recovery block scheme of fault tolerant techniques. Through this paper, we shall focus on build-or-buy decision for an APS in order to facilitate optimal component selection thereby, maximizing the reliability and minimizing the overall cost and source lines of code of the entire system. Further, since the proposed problem has incompleteness and unreliability of input information such as execution time and cost, hence, the environment in the proposed model is taken as fuzzy. © 2013 World Scientific Publishing Company.

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