94 research outputs found

    Joint Energy Efficient and QoS-aware Path Allocation and VNF Placement for Service Function Chaining

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    Service Function Chaining (SFC) allows the forwarding of a traffic flow along a chain of Virtual Network Functions (VNFs, e.g., IDS, firewall, and NAT). Software Defined Networking (SDN) solutions can be used to support SFC reducing the management complexity and the operational costs. One of the most critical issues for the service and network providers is the reduction of energy consumption, which should be achieved without impact to the quality of services. In this paper, we propose a novel resource (re)allocation architecture which enables energy-aware SFC for SDN-based networks. To this end, we model the problems of VNF placement, allocation of VNFs to flows, and flow routing as optimization problems. Thereafter, heuristic algorithms are proposed for the different optimization problems, in order find near-optimal solutions in acceptable times. The performance of the proposed algorithms are numerically evaluated over a real-world topology and various network traffic patterns. The results confirm that the proposed heuristic algorithms provide near optimal solutions while their execution time is applicable for real-life networks.Comment: Extended version of submitted paper - v7 - July 201

    Enhanced catalytic activity of natural hematite-supported ppm levels of Pd in nitroarenes reduction

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    In this work, Pd NPs supported on amine-modified natural hematite have been prepared and characterized. Using this simple catalyst, nitroaromatic compounds as a major cause of industrial pollution were reduced to corresponding amines with ppm levels of Pd in the presence of designer surfactant TPGS-750-M and NaBH4 at room temperature in aqueous media. Synergistic effect between hematite and Pd is responsible for the observed enhanced catalytic activity. This catalyst was recycled for at least four times with a small decrease in the activity.The authors are grateful to Institute for Advanced Studies in Basic Sciences (IASBS) Research Council and Iran National Science Foundation (INSF-Grant number of 97021804) for support of this work. We also gratefully acknowledge financial support from the Spanish Ministerio de EconomĂ­a y Competitividad (MINECO) (projects CTQ2013-43446-P and CTQ2014-51912-REDC), the Spanish Ministerio de EconomĂ­a, Industria y Competitividad, Agencia Estatal de InvestigaciĂłn (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, EU) (projects CTQ2016-76782-P and CTQ2016-81797-REDC), the Generalitat Valenciana (PROMETEOII/2014/017) and the University of Alicante

    Starch functionalized creatine for stabilization of gold nanoparticles: Efficient heterogeneous catalyst for the reduction of nitroarenes

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    Selective reduction of nitroaromatic pollutants into amines with recoverable and reusable heterogeneous catalysts is highly desirable. Herein, we prepared and characterized an efficient novel catalyst comprising 4 nm size Au nanoparticles supported on creatine modified starch. Using this catalyst, efficient reduction of nitroarenes into amines at room temperature in aqueous media was achieved. The presence of creatine in the structure of the catalyst plays important role in amount of Au loading, efficiency of the catalyst, recycling times, and leaching of Au compared to starch supported Au without creatine.The authors are grateful to Institute for Advanced Studies in Basic Sciences (IASBS) Research Council and Iran National Science Foundation (INSF-Grant number of 97021804) for support of this work. We also gratefully acknowledge financial support from the Spanish Ministerio de Economía y Competitividad (MINECO) (projects CTQ2013-43446-P and CTQ2014-51912-REDC), the Spanish Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, EU) (projects CTQ2016-76782-P and CTQ2016-81797-REDC), the Generalitat Valenciana (PROMETEOII/2014/017) and the University of Alicante

    Distributed coloring of the graph edges

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    IADE: An Improved Differential Evolution Algorithm to Preserve Sustainability in a 6G Network

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    Differential evolution (DE) algorithm is utilized to find an optimized solution in multidimensional real applications like 5G/6G networked devices and support unlimited connectivity for terrestrial networks due to high efficiency, robustness, and easy achievements. With the development of new emerging networks and the rise of big data, the DE algorithm encounters a series of challenges, such as the slow convergence rate in late iteration, strong parameter dependence, and easiness to fall into local optimum. These issues exponentially increase the energy and power consumption of communications and computing technologies in 5G/6G network like a networked data center. To address this and leverage a practical solution, this paper introduces IADE, an improved adaptive DE algorithm, to solve the problems mentioned earlier. IADE improves the scaling factor, crossover probability, variation, and selection strategy of the DE algorithm. In IADE, the parameters adaptively adjusted with the population's iterative evolution to meet the parameter's different requirements values of network steering traffic in each period. Numerous experiments are carried out through the benchmark function to evaluate the performance of IADE, and the results obtained from the experiment illustrate that IADE surpasses the benchmark algorithms in terms of solution accuracy and convergence speed for large tasks around 10%, respectively

    PAKIT: Proactive Authentication and Key Agreement Protocol for Internet of Things

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    Internet of Things (IoT) holds great promise for many life-improving applications like health-care systems. In IoT systems, providing secure authentication and key agreement scheme that considers compromised entities is an important issue. State-of-the-arts tackle this problem, but they fail to address compromised entity attack and have high computation cost. Motivated by these considerations, in this paper, we propose an energy-efficient proactive authentication and key agreement scheme called PAKIT for IoT systems. The security of PAKIT scheme is validated using the ProVerif tool. Moreover, the efficiency of PAKIT is compared with the predecessor schemes proposed for IoT systems. The results of the experiments show that PAKIT is efficient and suitable for real-world IoT applications by utilizing lightweight functions, such as hash and XOR

    A New Secure Data Dissemination Model in Internet of Drones

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    Data Dissemination is the distribution of data/statistics to the end users. With the adoption of Internet of Drones (IoD) environment for data dissemination, an efficient scheme is proposed which provides data integrity, identity anonymity, authentication, authorization, accountability (AAA) to the system model. We propose a system model having Ethereum based public blockchain distributed network in order to secure drone communication for the data collection and transmission. The proposed model provides secure communication between the drones and the users in a decentralized way. In this paper, blockchain technology is used for the storage of collected data from the drones and update the information into the distributed ledgers to reduce the burden of drones. It also provides integrity, authentication, and authorization to the collected data by the drones in the system model. Motivated by this consideration, the goal of this paper is threefold. First, we select a forger node from the number of drones. Second, we create blocks and validate their processes. Third, we provide secure data dissemination by applying Proof-of-Stake consensus mechanism. Afterward, we evaluate the security of the presented system model compared against the corresponding ones of some state-of-the-art in terms of communication time/cost. The results confirm that our system model is reliable and scalable for data dissemination in the IoD environment

    PGSW-OS: a novel approach for resource management in a semantic web operating system based on a P2P grid architecture

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    A web operating system is an operating system that users can access from any hardware at any location. A peer-to-peer (P2P) grid uses P2P communication for resource management and communication between nodes in a grid and manages resources locally in each cluster, and this provides a proper architecture for a web operating system. Use of semantic technology in web operating systems is an emerging field that improves the management and discovery of resources and services. In this paper, we propose PGSW-OS (P2P grid semantic Web OS), a model based on a P2P grid architecture and semantic technology to improve resource management in a web operating system through resource discovery with the aid of semantic features. Our approach integrates distributed hash tables (DHTs) and semantic overlay networks to enable semantic-based resource management by advertising resources in the DHT based upon their annotations to enable semantic-based resource matchmaking. Our model includes ontologies and virtual organizations. Our technique decreases the computational complexity of searching in a web operating system environment. We perform a simulation study using the Gridsim simulator, and our experiments show that our model provides enhanced utilization of resources, better search expressiveness, scalability, and precision. © 2014 Springer Science+Business Media New York
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