Browsing by Author "Ben Othman, Jalel"

Now showing 1 - 9 of 9
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    CCS_WHMS: A Congestion Control Scheme for Wearable Health Management System
    (Springer Link, 2015-10-21) Kafi, Mohamed Amine; Ben Othman, Jalel; Bagaa, Miloud; Badache, Nadjib
    Wearable computing is becoming a more and more attracting field in the last years thanks to the miniaturisation of electronic devices. Wearable healthcare monitoring systems (WHMS) as an important client of wearable computing technology has gained a lot. Indeed, the wearable sensors and their surrounding healthcare applications bring a lot of benefits to patients, elderly people and medical staff, so facilitating their daily life quality. But from a research point of view, there is still work to accomplish in order to overcome the gap between hardware and software parts. In this paper, we target the problem of congestion control when all these healthcare sensed data have to reach the destination in a reliable manner that avoids repetitive transmission which wastes precious energy or leads to loss of important information in emergency cases, too. We propose a congestion control scheme CCS_WHMS that ensures efficient and fair data delivery while used in the body wearable system part or in the multi-hop inter bodies wearable ones to get the destination. As the congestion detection paradigm is very important in the control process, we do experimental tests to compare between state of the art congestion detection methods, using MICAz motes, in order to choose the appropriate one for our scheme.
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    CCS_WHMS: A Congestion Control Scheme for Wearable Health Management System
    (Springer US, 2015-12) Kafi, Mohamed Amine; Ben Othman, Jalel; Bagaa, Miloud; Badache, Nadjib
    Wearable computing is becoming a more and more attracting field in the last years thanks to the miniaturisation of electronic devices. Wearable healthcare monitoring systems (WHMS) as an important client of wearable computing technology has gained a lot. Indeed, the wearable sensors and their surrounding healthcare applications bring a lot of benefits to patients, elderly people and medical staff, so facilitating their daily life quality. But from a research point of view, there is still work to accomplish in order to overcome the gap between hardware and software parts. In this paper, we target the problem of congestion control when all these healthcare sensed data have to reach the destination in a reliable manner that avoids repetitive transmission which wastes precious energy or leads to loss of important information in emergency cases, too. We propose a congestion control scheme CCS_WHMS that ensures efficient and fair data delivery while used in the body wearable system part or in the multi-hop inter bodies wearable ones to get the destination. As the congestion detection paradigm is very important in the control process, we do experimental tests to compare between state of the art congestion detection methods, using MICAz motes, in order to choose the appropriate one for our scheme.
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    Congestion Control Protocols in Wireless Sensor Networks: A Survey
    (2014-03-05) Kafi, Mohamed Amine; Djenouri, Djamel; Ben Othman, Jalel; Badache, Nadjib
    The performance of wireless sensor networks (WSN) is affected by the lossy communication medium, application diversity, dense deployment, limited processing power and storage capacity, frequent topology change. All these limitations provide significant and unique design challenges to data transport control in wireless sensor networks. An effective transport protocol should consider reliable message delivery, energy-efficiency, quality of service and congestion control. The latter is vital for achieving a high throughput and a long network lifetime. Despite the huge number of protocols proposed in the literature, congestion control in WSN remains challenging. A review and taxonomy of the state-of-the-art protocols from the literature up to 2013 is provided in this paper. First, depending on the control policy, the protocols are divided into resource control vs. traffic control. Traffic control protocols are either reactive or preventive (avoiding). Reactive solutions are classified following the reaction scale, while preventive solutions are split up into buffer limitation vs. interference control. Resource control protocols are classified according to the type of resource to be tuned.
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    Congestion Detection Strategies in Wireless sensor Networks: A Comparative Study with Testbed Experiments
    (CERIST, 2014-07-07) Kafi, Mohamed Amine; Djenouri, Djamel; Ben Othman, Jalel; Ouadjaout, Abdelraouf; Badache, Nadjib
    Event based applications of Wireless Sensor Networks (WSNs) are prone to tra c congestion, where unpredicted event detection yields simultaneous generation of tra c at spatially co-related nodes, and its propagation towards the sink. This results in loss of information and waste energy. Early congestion detection is thus of high importance in such WSN applications to avoid the propagation of such a problem and to reduce its consequences. Di erent detection metrics are used in the congestion control literature. However, a comparative study that investigates the di erent metrics in real sensor motes environment is missing. This paper focuses on this issue and compares some detection metrics in a testbed network with MICAz motes. Results show the e ectiveness of each method in di erent scenarios and concludes that the combination of bu er length and channel load constitute the better candidate for early and fictive detection.
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    Congestion Detection Strategies in Wireless Sensor Networks: A Comparative Study with Testbed Experiments
    (Elsevier, 2014) Kafi, Mohamed Amine; Djenouri, Djamel; Ben Othman, Jalel; Ouadjaout, Abdelraouf; Badache, Nadjib
    Event based applications of Wireless Sensor Networks (WSNs) are prone to traffic congestion, where unpredicted event detection yields simultaneous generation of traffic at spatially co-related nodes, and its propagation towards the sink. This results in loss of information and waste energy. Early congestion detection is thus of high importance in such WSN applications to avoid the propagation of such a problem and to reduce its consequences. Different detection metrics are used in the congestion control literature. However, a comparative study that investigates the different metrics in real sensor motes environment is missing. This paper focuses on this issue and compares some detection metrics in a testbed network with MICAz motes. Results show the effectiveness of each method in different scenarios and concludes that the combination of buffer length and channel load constitute the better candidate for early and fictive detection.
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    Interference-aware Congestion Control Protocol for Wireless Sensor Networks
    (Elsevier, 2014-09) Kafi, Mohamed Amine; Djenouri, Djamel; Ben Othman, Jalel; Ouadjaout, Abdelraouf; Bagaa, Miloud; Lasla, Noureddine; Badache, Nadjib
    This paper deals with congestion and interference control in wireless sensor networks (WSN), which is essential for improving the throughput and saving the scarce energy in networks where nodes have different capacities and traffic patterns. A scheme called IACC (Interference-Aware Congestion Control) is proposed. It allows maximizing link capacity utilization for each node by controlling congestion and interference. This is achieved through fair maximum rate control of interfering nodes in inter and intra paths of hot spots. The proposed protocol has been evaluated by simulation, where the results rival the effectiveness of our scheme in terms of energy saving and throughput. In particular, the results demonstrate the protocol scalability and considerable reduction of packet loss that allow to achieve as high packet delivery ratio as 80% for large networks.
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    Interference-Aware Congestion Control Protocol for Wireless Sensor Networks
    (CERIST, 2014-07-07) Kafi, Mohamed Amine; Djenouri, Djamel; Ben Othman, Jalel; Ouadjaout, Abdelraouf; Bagaa, Miloud; Lasla, Noureddine; Badache, Nadjib
    This paper deals with congestion and interference control in wireless sensor networks (WSN), which is essential for improving the throughput and saving the scarce energy in networks where nodes have di erent capacities and tra c patterns. A scheme called IACC (Interference-Aware Congestion Control ) is proposed. It allows maximizing link capacity utilization for each node by controlling congestion and interference. This is achieved through fair maximum rate control of interfering nodes in inter and intra paths of hot spots. The proposed protocol has been evaluated by simulation, where the results rival the e ectiveness of our scheme in terms of energy saving and throughput. In particular, the results demonstrate the protocol scalability and considerable reduction of packet loss that allows to achieve as high packet delivery ratio as 80% for large networks.
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    Performance analysis and evaluation of REFIACC using queuing networks
    (Elsevier, 2017-02) Kafi, Mohamed Amine; Ben Othman, Jalel; Mokdad, Lynda; Badache, Nadjib
    Wireless Sensor Networks (WSN) utilisation is characterised by its dense deployment in order to fulfil the monitoring tasks. This density of communication leads to interference and congestion. In a previous work, a schedule scheme dubbed REFIACC (Reliable, Efficient, Fair and Interference Aware Congestion Control), that takes into account interferences and different links capacities in order to avoid packet loss due congestion, was proposed. REFIACC idea was validated using comparative simulations. In this study, REFIACC scheduling scheme was modelled using Markov chains. The modelling concerns queue length evolution and global system throughput. Different hypothesis details for queue length monitoring, according to application motivation, have led to many variants of models. The evaluation of the model using MATLAB has shown its effectiveness concerning packet reception ratio and reception overhead.
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    REFIACC: Reliable, Efficient, Fair and Interference-Aware Congestion Control Protocol for Wireless Sensor Networks
    (Elsevier, 2016-05-28) Kafi, Mohamed Amine; Ben Othman, Jalel; Ouadjaout, Abdelraouf; Bagaa, Miloud; Badache, Nadjib
    The recent wireless sensor network applications are resource greedy in terms of throughput and network reliability. However, the wireless shared medium leads to links interferences in addition to wireless losses due to the harsh environment. The effect of these two points translates on differences in links bandwidth capacities, lack of reliability and throughput degradation. In this study, we tackle the problem of throughput maximization by proposing an efficient congestion control-based schedule algorithm, dubbed REFIACC (Reliable, Efficient, Fair and Interference-Aware Congestion Control) protocol. REFIACC prevents the interferences and ensures a high fairness of bandwidth utilization among sensor nodes by scheduling the communications. The congestion and the interference in inter and intra paths hot spots are mitigated through tacking into account the dissimilarity between links' capacities at the scheduling process. Linear programming is used to reach optimum utilization efficiency of the maximum available bandwidth. REFIACC has been evaluated by simulation and compared with two pertinent works. The results show that the proposed solution outperforms the others in terms of throughput and reception ratio (more than 80%) and can scale for large networks.