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Item A critical review of quality of service models in mobile ad hoc networks(Inderscience Enterprises Ltd, 2019) Bouchama, Nadir; Aïssani, Djamil; Djellab, Natalia; Nouali-Taboudjemat, NadiaQuality of service (QoS) provisioning in mobile ad hoc networks (MANETs) consists of providing a complex functionality in a harsh environment where resources are scarce. Thus, it is very challenging to build an efficient solution to address this issue. The proposed solutions in the literature are broadly classified into four categories, namely: QoS routing protocols, QoS signalling, QoS-aware MAC protocols and QoS models, which are the main concern of our study. The contribution of this paper is threefold: Firstly, we propose a set of guidelines to deal with the challenges facing QoS models design in ad hoc networks. Secondly, we propose a new taxonomy for QoS models in ad hoc networks. Finally, we provide an in-depth survey and discussion of the most relevant proposed frameworks.Item Lifetime-Aware Backpressure : A New Delay-Enhanced Backpressure-Based Routing Protocol(IEEE, 2019-03) Kabou, Abdelbaset; Nouali-Taboudjemat, Nadia; Djahel, Soufiene; Yahiaoui, Saïd; Nouali, OmarDynamic backpressure is a highly desirable family of routing protocols known for their attractive mathematical properties. However, these protocols suffer from a high end-to-end delay making them inefficient for real-time traffic with strict end-to-end delay requirements. In this paper, we address this issue by proposing a new adjustable and fully distributed backpressure-based scheme with low queue management complexity, named Lifetime-Aware Backpressure (LTA-BP). The novelty in the proposed scheme consists in introducing the urgency level as a new metric for service differentiation among the competing traffic flows in the network. Our scheme not just significantly improves the quality of service provided for real-time traffic with stringent end-to-end delay constraints, but interestingly protects also the flows with softer delay requirements from being totally starved. The proposed scheme has been evaluated and compared against other state-of-the-art routing protocol, using computer simulation, and the obtained results show its superiority in terms of the achieved end-to-end delay and throughput.Item Toward a new Backpressure-based framework to Enhance Situational Awareness in Disaster Response(IEEE ICT-DM-2017, 2017-12-11) Kabou, Abdelbaset; Nouali-Taboudjemat, Nadia; Nouali, OmarCrises generate intense need to communication not just as a panic reaction to crisis, but also due the critical need for communication in order to better coordinate during response activities. In the afterward of a disaster, the lack of resources to handle this increase of data, due to the fragility of network infrastructures, leads to network congestion or overload. The results is that critical data are prevented from reaching decision makers, which has a direct impact on situational-awareness. To overcome this problem, we propose a new cross layer architecture for Wireless Mesh Network with a twofold objective: one, to include a filtering system able to identify the most critical data and two, to propose a routing layer with the capacity to prioritize these data while ensuring the stability and throughput optimality of the whole network. The proposed solution combines both by proposing an adjustable and fully distributed version of the high throughput efficient Backpressure routing protocol, with a geolocation and role-based filtering and prioritizing system. Both components collaborate in a way to identify and send most critical data, using a lower end-to-end delay, without however starving less critical data. Extensive experiments, using NS-3 simulator, are used to validate the proposal and confirm the high impact of the introduced ideasItem New GPU-based Swarm Intelligence Approach For Reducing Big Association Rules Space(CERIST, 2017-06-14) Djenouri, Youcef; Bendjoudi, Ahcène; Djenouri, Djamel; Belhadi, Asma; Nouali-Taboudjemat, NadiaThis paper deals with exploration and mining of association rules in big data, with the big challenge of increasing computation time. We propose a new approach based on meta-rules discovery that gives to the user the summary of the rules’ space through a meta-rules representation. This allows the user to decide about the rules to take and prune. We also adapt a pruning strategy of our previous work to keep only the representatives rules. As the meta-rules space is much larger than the rules space, two approaches are proposed for efficient exploitation. The first one uses a bees swarm optimization method in the meta-rules discovery process, which is extended using GPU-based parallel programming to form the second one. The sequential version has been first tested using medium rules set, and the results show clear improvement in terms of the number of returned meta-rules. The two versions have then been compared on large scale rules sets, and the results illustrate the acceleration on the summarization process by the parallel approach without reducing the quality of resulted meta-rules. Further experiments on Webdocs big data instances reveal that the proposed method of pruning rules by summarizing meta-rules considerably reduces the association rules space compared to state-of-the-art association rules mining-based approaches.Item Installation et configuration d’une solution de détection d’intrusions sans fil (Kismet)(CERIST, 2011-06) Lounis, Karim; Babakhouya, Abdelaziz; Nouali-Taboudjemat, NadiaLes réseaux sans fil (Wi-Fi, norme 802.11) offrent plusieurs avantages ; notamment en terme de mobilité, coût, débit et facilité de déploiement. Cependant, ils sont par nature plus sensibles aux problèmes de sécurité. Les mécanismes de sécurité (WEP, WPA, WPA2) ne permettent pas de se prévenir contre tous les problèmes de sécurité. En effet, les bornes Wi-Fi restent toujours vulnérables aux intrusions : attaque de déni de service, rogue AP, attaque de dé-authentification. Dans cette optique, il est conseillé de surveiller régulièrement l'activité du point d'accès sans fil afin de détecter les activités anormales sur le réseau et de les signaler sous forme d’ALERTES. Ce rapport présent les détails techniques d’installation et de configuration d’une solution de détection d’intrusion pour un réseau Wi-Fi. Cette solution se base sur des logiciels open source (Linux, Kismet, OPENWRT, DD-WRT, SWATCH) et une série de matériels sans fil (routeur Linksys WRT54GL et carte réseau sans fil).Item Locating Emergency Responders using Mobile Wireless Sensor Networks(CERIST, 2012-07) Benkhelifa, Imane; Nouali-Taboudjemat, NadiaL'intervention d'urgence dans la gestion des catastrophes en utilisant les réseaux de capteurs sans fils est devenue récemment un intérêt de nombreux chercheurs du monde entier. Cet intérêt provient du nombre croissant de catastrophes et de crises (naturelles ou humaines) qui touchent des millions de vies ainsi que l'utilisation facile des nouvelles technologies pas cher. Ce document arrive avec un algorithme pour localiser les intervenants d'urgence et les secouristes en utilisant capteurs attachés aux secouristes. La solution proposée est très efficace et rapidement déployable et ne nécessite aucune infrastructure préinstallé. La solution est basée sur la prédiction des déplacements des secouristes en se basant sur des estimations de position précédentes. L'évaluation de notre solution montre que notre technique prend avantage de la prédiction d'une manière plus efficace que les solutions précédentes.Item Infrastructure de communication sans fil avec qualité de service pour la gestion de crises et catastrophes(CERIST, 2016-11) Kabou, Abdelbasset; Nouali-Taboudjemat, Nadia; Nouali, OmarLa Qualité de service (Quality of Service ou QoS) est un terme largement utilisé dans le domaine des technologies de communication. Dans les recommandations E.800, le CCITT (United Nations Consultative Committee for International Telephony and Telegraphy) défini la qualité de service comme : “Ensemble des effets portant sur les performances d’un service de communication et qui détermine le degré de satisfaction d’un utilisateur de ce même service”. Un intérêt particulier est porté dans ce rapport à la problématique du maintien de la QoS pour les applications multimédia. Ce type d'applications est très sensible aux variations des conditions régissant le réseau. Des métriques comme la bande passante, le taux de perte des paquets, la latence, la gigue ou des mécanismes tels le contrôle d’admission, les protocoles de signalisation, etc., sont de très grande importance pour ces applications et plus particulièrement durant une situation d'urgence. Ce rapport donne un aperçu de nos travaux sur la QoS des réseaux déployés en situation d'urgence.Item Multi and Many-core Parallel B&B approaches for the Blocking Job Shop Scheduling Problem(2016-07) Dabah, Adel; Bendjoudi, Ahcène; Ait Zai, Abdelhakim; El Baz, Didier; Nouali-Taboudjemat, NadiaIn this paper, we propose three approaches to accelerate the B&B execution time using Multi and Many-core systems to solve the NP-hard Blocking Job Shop Scheduling problem (BJSS). The first approach is based on Master/Worker paradigm where the workers independently explore the branches sent by the master. The second approach is a node-based parallelization that does not change the design of the B&B algorithm, except that the bounding process is faster since it is calculated in parallel using several threads organized in one GPU block. The third approach is a Multi-Core CPU/GPU hybridization that benefits from the power of both the CPU-cores and the GPU at the same time. This hybridization is based on concurrent kernels execution provided by Nvidia Multi process Service (MPS) i.e. each host process (Master or Worker) launches his own kernel to accelerate the bounding process on GPU. The obtained results using Taillard instances confirm the efficiency of our proposals. The first two approaches are respectively three and eighteen times faster compared to the sequential version. The results of the hybrid approach show a relative speedup over ninety times as compared to the sequential approach and therefore prove the advantage of using both the CPU-cores and the GPU at the same time.Item Data reordering for minimizing threads divergence in GPU-based evaluating association rules(CERIST, 2015-03-26) Djenouri, Youcef; Bendjoudi, Ahcène; Mehdi, Malika; Habbas, Zineb; Nouali-Taboudjemat, NadiaThis last decade, the success of Graphics Processor Units (GPUs) has led researchers to launch a lot of works on solving large complex problems by using these cheap and powerful architecture. Association Rules Mining (ARM) is one of these hard problems requiring a lot of computational resources. Due to the exponential increase of data bases size, existing algorithms for ARM problem become more and more inefficient. Thus, research has been focusing on parallelizing these algorithms. Recently, GPUs are starting to be used to this task. However, their major drawback is the threads divergence problem. To deal with this issue, we propose in this paper an intelligent strategy called Transactions- based Reordering "TR" allowing an efficient evaluation of association rules on GPU by minimizing threads divergence. This strategy is based on data base re-organization. To validate our proposition, theoretical and experimental studies have been carried out using well-known synthetic data sets. The results are very promising in terms of minimizing the number of threads divergence.Item Data reordering for minimizing threads divergence in GPU-based evaluating association rules(2015-06) Djenouri, Youcef; Bendjoudi, Ahcène; Mehdi, Malika; Habbas, Zineb; Nouali-Taboudjemat, NadiaThis last decade, the success of Graphics Processor Units (GPUs) has led researchers to launch a lot of works on solving large complex problems by using these cheap and powerful architecture. Association Rules Mining (ARM) is one of these hard problems requiring a lot of computational resources. Due to the exponential increase of data bases size, existing algorithms for ARM problem become more and more inefficient.Thus, research has been focusing on parallelizing these algorithms. Recently, GPUs are starting to be used to this task. However, their major drawback is the threads divergence problem. To deal with this issue, we propose in this paper an intelligent strategy called transactions-based Reordering ”TR” allowing an efficient evaluation of association rules on GPU by minimizing threads divergence. This strategy is based on data base re-organization. To validate our proposition, theoretical and experimental studies have been carried out using well-known synthetic datasets. The results are very promising in terms of minimizing the number of threads divergence.