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Background: Cloud computing environment is a novel paradigm in which the services are hosted, delivered and managed over the internet. Tasks scheduling problem in the cloud has become a very interesting research area. However, the problem is more complex and challenging due to the dynamic nature of cloud and users’ needs as well as cloud providers’ requirements including the quality of service, users’ priorities and computing capabilities. Objective: The main objective is to solve the problem of tasks scheduling through an algorithm which can not only improves the client satisfaction, but also allows cloud service provider to gain maximum profit and ensure that the cloud resources are utilized efficiently. Method: (a) Optimization of the waiting time and the queue length. Methods: (a) Optimization of the waiting time and the queue length. (b) Distribution of all requests into a novel queueing system in a dynamic manner based on a decision threshold. (c) Assignment of requests to VMs based on Particle Swarm Optimization and Simulated Annealing algorithms. (d) Incorporation of the priority constraint in the scheduling process by considering three priorities levels including the tasks, queues and VMs. Results: The results comparison of our algorithm with particle swarm optimization and First Come First Serve algorithms demonstrate the effectiveness of our algorithm in terms of waiting time, makespan, resources utilization and degree of imbalance. Conclusion: This study introduces an efficient strategy to schedule users’ tasks by using dynamic dispatch queues and particle swarm optimization with simulated annealing algorithms. Moreover, it incorporates the priority issue in the scheduling process.

Finding a career opportunity for a young job seeker is a challenge to every graduate; employability is a factor to maintain social cohesion, and political stability, to reduce the crisis of confidence in the education system. Answering the employability problematic is a priority in the strategy of most countries, and which quite often drives the public and scientific debates. The era of Big Data is now in full force because the world is changing, thanks to advances in communication technologies, people and objects are increasingly interconnected, not just a part of the time, but almost all the time. People are starting to use many connected objects, such as cars, phones, they are becoming more involved in social networks. Data is generated almost all the time, giving this huge amount of data ready to be used and stored. Storing this data is not the major problem; extraction of the hiding patterns between this data is actually the objective. The use of big data and data mining will give the opportunity to decision-makers to make a lot of improvements in the employability domain. In this paper, we present a data mining approach to predict employability in Morocco; we present it in a form of a graph, with phases, explaining every phase and what it includes in details, from data collection till the visualization of the results.

Wireless Sensor Network (WSN) is consisting of independent and distributed sensors to monitor physical or environmental conditions, such as temperature, sound, pressure, etc. The most crucial and fundamental challenge facing WSN is security. Due to minimum capacity in-term of memory cost, processing and physical accessibility to sensors devices the security attacks are problematic. They are mostly deployed in open area, which expose them to different kinds of attacks. In this paper, we present an illustration of different attacks and vulnerabilities in WSN. Then we proposed a new lightweight cryptography algorithm for identifying compromised node in WSN called Leap Enhanced. Our evaluations on TOSSIM give a precise and detailed idea of the extra cost of consumption of resources needed to ensure the high level of expected security compared to other cryptography schemes in literature., in French

Recently, Wireless Sensor Networks (WSNs) grow to be one of the dominant technology trends; new needs are continuously emerging and demanding more complex constraints in a duty cycle, such as extend the life time communication . The MAC layer plays a crucial role in these networks; it controls the communication module and manages the medium sharing. In this work we use OSC-MAC tackles combining with the performance of cooperative transmission (CT) in multi-hop WSN and the Wi-Lem technology

Wireless Sensor Network (WSN) is consisting of independent and distributed sensors to monitor physical or environmental conditions, such as temperature, sound, pressure, etc. However, the limited resources of sensors and hostile environments in which they could be deployed, make this type of networks vulnerable to several types of attacks similar to those occurring in ad hoc networks. The most crucial and fundamental challenge that WSN is facing is security. The primary subject of all my work is to address this issue. Due to minimum capacity in term of memory cost, processing and physical accessibility to sensors devices the security attacks are problematic. They are mostly deployed in open area so are more exposed to different kinds of attacks. They must be designed in a way to successfully recover itself from different kinds of attacks. In this paper, we proposed a new lightweight cryptography algorithm based on LEAP+. Our evaluations on TOSSIM give a precise and detailed idea of the extra cost of consumption of resources needed to ensure the high level of expected security., 6 pages, 5 figures, Advanced Information Technology, Services and Systems (AIT2S) Conference 2015

In this paper, we describe the impact of black-hole attack on LEACH protocol and direct transmission using C++ language and some tools from ns3. The results are showed in the number of packet received by the base station; and we try to protect the network from this type of network using the minimum energy and less modification in the original algorithm.

Wireless Sensor Network (WSN) is consisting of independent and distributed sensors to monitor physical or environmental conditions, such as temperature, sound, pressure, etc. The most crucial and fundamental challenge facing WSN is security. Due to minimum capacity in-term of memory cost, processing and physical accessibility to sensors devices the security attacks are problematic. They are mostly deployed in open area, which expose them to different kinds of attacks. In this paper, we present an illustration of different attacks and vulnerabilities in WSN. Then we describe and analyze security requirement, countermeasures based on cryptography mechanisms in literature. Finally, we present possible directions in future research., Comment: 9 pages, 5 figures, Mediterranean Telecommunications Journal, Vol. 6, N{\deg} 2, June 2016

Wireless Sensor Network (wsn) performances have progressed over the last few years, aiming at expanding the lifetime nodes. Among the important studied parts on wsn is the congestion degree that can be identified by several algorithms such as HTAP (Hierarchical Tree Alternative Path), which is the target in the current study. It is important to mention that besides the variations observed between the four HTAP deployments of this classical algorithm ( detailed on the rest of paper ) , there is a possibility that other factors, such as energy efficiency, network lifetime are affected by the node displacements in the HTAP phases ( in case of the route change caused by the isolated dead nodes to the sink ) , which give the idea to reduce this undesirable problem by designing a new algorithm called Hierarchical Tree Congestion degree with Speed sending and Sum costs link Quality (HTCSLQ) by reducing the energy consumption , according to the choice of the lower Congestion degree , optimal Speed sending and Sum costs link Quality values from the source to destination.

Today the world is moving towards wireless system. Wireless networks are gaining popularity to its peak today, as the users want wireless connectivity irrespective of their geographic position. Vehicular ad-hoc networks (VANETs) are considered to be the special application of infrastructure-less wireless Mobile ad-hoc network (MANET). In these networks, vehicles are used as nodes. In this paper, we examine and analyze the performance of Ad-hoc On-Demand (AODV), Dynamic Source Routing (DSR) and Destination-Sequenced Distance Vector (DSDV) routing in terms of Packet Delivery Ratio, Average End to End Delay, Latency and Throughput. The objective of this study is to find the best routing protocol over all circumstances. Based on our validated results, AODV performs the best among all evaluated protocols.

In wired networks there are different physical devices routing the traffic centrally. By consequence, we can create paths in the network by using multiple management rules, but in Ad-Hoc network nodes this work must be done in an autonomous way. For that there are three types of routing protocol proactive, reactive and hybrid. The first one continuously calculates the possible paths to be available at the time of transmission. The second one creates the roads only when they are needed. And the last one is a combination between the two methods. In this study we will focus on three routing protocols AODV, OLSR and ZRP; and compare their performance in terms of loss packets and energy efficient.

In mobile Ad-Hoc networks, each node of the network must contribute in the process of communication and routing. However this contribution can expose the network to several types of attackers. In this paper, we study the impact of one attack called BLACK-HOLE, on Ad hoc On-Demand Distance Vector routing protocol. In this attack a malicious node can be placed between two or several nodes, and begin dropping all packets from a source and breaking communications between nodes. The vulnerability of the route discovery packets is exploited by the attacker with a simple modification in the routing protocol, in order to control all the traffic between nodes. In this study we simulate the attack with NS2, taking into account the mobility of the network and the attacker, the position of the attacker and finally the number of the attackers. We will also see the impact of this attack in a higher number of loss packet compared with AODV in normal situation.