Hassine Moungla

ubiSOAP: A Service Oriented Middleware for Seamless Networking

The computing and networking capacities of todays wireless portable devices allow for pervasive services, which are seamlessly networked. Indeed, wireless handheld devices now embed the necessary resources to act as both service clients and providers. However, the seamless networking of services remains challenged by the inherent mobility and resource constraints of devices, which make services a priori highly volatile. This paper discusses the design, implementation and experimentation of the ubi SOAP service-oriented middleware, which leverages wireless networking capacities to effectively enable the seamless networking of services. ubi SOAP specifically defines a layered communication middleware that underlies standard SOAP-based middleware, hence supporting legacy services while exploiting nowadays pervasive connectivity.

Coexistence improvement of wearable body area network (WBAN) in medical environment

Wireless body area network (WBAN) witness an upward interest in several domain. Mainly, the medical domain takes advantages from the health service facility, the high flexibility and the mobility. However, interferences from coexisting wireless networks may lose critical informations and greatly affect on network reliability. In this paper, we are conducting to improve coexistence between WBAN based IEEE 802.15.4 protocol and WIFI. We adopt multi-hop routing to ensure reliability, connectivity and battery life. Then we investigate different effects of transmit power, transmission frequency and packet size on WBAN performances under heavy and real interferences circumstances. We propose a well suited model and simple adaptive algorithm which adjust dynamically its parameters with received performances indicators.

Conflict detection and resolution in QoS policy based management

In this paper, we present our policy based rule representation for a Diffserv network and show how they are translated and downloaded into the network element. One common problem in specifying rules for policy-based networks is the conflict detection problem, where rules may contradict or duplicate each other. We explore the algorithmic issues related to conflict detection problem and present a conflict detection algorithm. Performance results are also presented. An interactive Java-based policy management tool editor was designed for specifying the rules and detecting the conflicts among rules

Interference avoidance algorithm (IAA) for multi-hop wireless body area network communication

In this paper, we propose a distributed multi-hop interference avoidance algorithm, namely, IAA to avoid co-channel interference inside a wireless body area network (WBAN). Our proposal adopts carrier sense multiple access with collision avoidance (CSMA/CA) between sources and relays and a flexible time division multiple access (FTDMA) between relays and coordinator. The proposed scheme enables low interfering nodes to transmit their messages using base channel. Depending on suitable situations, high interfering nodes double their contention windows (CW) and probably use switched orthogonal channel. Simulation results show that proposed scheme has far better minimum SINR (12dB improvement) and longer energy lifetime than other schemes (power control and opportunistic relaying). Additionally, we validate our proposal in a theoretical analysis and also propose a probabilistic approach to prove the outage probability can be effectively reduced to the minimal.

A power harvesting, dynamic and reliable wireless body area networks model deployment for health care applications

This paper presents our conducting research and describes a new optimal deployment model for medical wireless body area network (WBAN) sensor devices (without mobility) and the relevant possible trade-offs between coverage, connectivity and network life time. We also integrate the effect of interference in wireless medium, and try to devise many-to-one and many-to-many model, that minimize the interference throughout the network and thus increase signal quality of wireless communication. The decrease in interference also facilitates energy efficiency, by increasing reliability, i.e. success ratio of wireless links. Topologies generated from our proposed model exhibit minimum energy consumption at maximum sensing coverage. The results show that significant improvements of initial deployments using feasible and cost-efficient solutions are possible. Our model leads to significantly optimized initial network deployments which can be subsequently used with other existing optimization techniques in literature. Overall operational lifetime and sensing coverage of WBSNs are strongly improved by our suggested deployment model.

A Min-Max multi-commodity flow model for wireless body area networks routing

The increasing use of wireless networks and the constant miniaturization of electrical devices has empowered the development of Wireless Body Sensor Networks (WBSNs). The wireless nature of the network and the wide variety of sensors offer numerous new, practical and innovative applications to improve health care and the Quality of Life. WBSNs like any other sensor networks suffer limited energy resources and hence preserving the energy of the nodes is of great importance. Unlike typical sensor networks WBSNs have few and dissimilar sensors. In addition, an extremely low transmit power per node is needed to minimize interference to cope with health concerns and to avoid tissue heating which means that the existing solution for preserving energy in wireless sensor networks might not be efficient in WBSNs. Most of the attention has been given to the energy routing where energy awareness is an essential consideration. In this paper, we propose a Min-Max multi-commodity flow model for WBSNs which allows to prevent sensor node saturation, by imposing an equilibrium use of sensors during the routing process taking into account the specific characteristics of the wireless environment on the human body. The Min-Max objective is transformed to a Min objective by adding a set of constraints to the model. Based on the energy consumption for sending and receiving data and the available residual energy of nodes, the max-min based mathematical programming model is designed to find optimal routing. Simulation results show that the algorithm balances the energy consumption of nodes effectively and maximize the network lifetime.

Medium Access for Concurrent Traffic in Wireless Body Area Networks: Protocol Design and Analysis

Wireless body area networks have been deployed to monitor the health condition of patients. In these applications, multiple sensors are required to report real-time data to the sink such that a physician can diagnose accurately, particularly for intensive care patients, which boosts the convergecast traffic load and increases the collision probability. However, the existing protocols cannot effectively operate under such concurrent traffic load. To bridge this gap, we present a novel two-phase receiver-initiated medium access control (MAC) protocol for concurrent traffic based on asynchronous duty cycling, which is called C-MAC. Technically, C-MAC in the first phase employs carrier-sense multiple access with collision avoidance of the IEEE 802.15.6 standard and designs an ordering-based communication algorithm to effectively avoid collisions. Moreover, C-MAC enables sensor nodes to switch to standby mode to avoid idle listening and overhearing in the second phase. Furthermore, theoretically, we explicitly formulate the mathematical expressions of the random delay and energy consumption of C-MAC. Finally, we conduct extensive numerical analysis and simulation to demonstrate the correctness of theoretical results and the better effectiveness and efficiency of C-MAC than that of RI-MAC and A-MAC in terms of transmission delay and energy consumption.

A reliable and energy-efficient leader election algorithm for Wireless Body Area Networks

Wireless Body Area Networks (WBANs) which offer a variety of promising applications in the areas of medical and consumer electronics have been paid lots of attention. However, very limited work has been done on the network reliability combined with energy conservation in spite of their fundamental importance. In order to bridge this gap, we devote this paper to developing a reliable and energy-efficient leader election (REELE) algorithm for WBANs. To this end, technically, we first partition a WBAN into regions and build the reliability and energy consumption models. By the reliability analysis, we then propose a novel communication strategy for nodes and further derive the total energy consumption of a region. With the reliability and residual energy of a node and total energy consumption considered jointly, REELE algorithm can considerably enhance reliability and conserve energy. Extensive simulation results demonstrate the effectiveness and the efficiency of REELE in terms of longer network lifetime, better energy characteristics as well as higher reliability.

Flooding attacks detection in backbone traffic using power divergence

Flooding attacks detection in traffic of backbone networks requires generally the analysis of a huge amount of data with high accuracy and low complexity. In this paper, we propose a new scheme to detect flooding attacks in high speed networks. The proposed mechanism is based on the application of Power Divergence measures over Sketch data structure. Sketch is used for random aggregation of traffic, and Power Divergence is applied to detect deviations between current and established probability distributions of network traffic. We focus on tuning the parameter of Power Divergence to optimize the performance. We evaluate our approach using real Internet traffic traces, obtained from MAWI trans-Pacific wide transit link between USA and Japan. Our results show that the proposed approach outperforms existing solutions in terms of detection accuracy and false alarm ratio.

Distributed scheme for interference mitigation of WBANs using predictable channel hopping

When sensors of different coexisting wireless body area networks (WBANs) transmit at the same time using the same channel, a co-channel interference is experienced and hence the performance of the involved WBANs may be degraded. In this paper, we exploit the 16 channels available in the 2.4 GHz international band of ZIGBEE, and propose a distributed scheme that avoids interference through predictable channel hopping based on Latin rectangles, namely, CHIM. In the proposed CHIM scheme, each WBANs coordinator picks a Latin rectangle whose rows are ZIGBEE channels and columns are sensor IDs. Based on the Latin rectangle of the individual WBAN, each sensor is allocated a backup time-slot and a channel to use if it experiences interference such that collisions among different transmissions of coexisting WBANs are minimized. We further present a mathematical analysis that derives the collision probability of each sensors transmission in the network. In addition, the efficiency of CHIM in terms of transmission delay and energy consumption minimization are validated by simulations.