Nadia Nouali-Taboudjemat

Disaster Management Projects Using Wireless Sensor Networks: An Overview

There are numerous projects dealing with disaster management and emergency response that use wireless sensor networks technologies. Indeed, WSNs offer a good alternative compared to traditional ad hoc networks. Air pollution monitoring, forest fire detection, landslide detection, natural disaster prevention, industrial sense and control applications, dangerous gas leakage, water level monitoring, vibration detection to prevent an earthquake, radiation monitoring are examples of the WSN applications related to disaster management. This paper presents an overview of the recent projects using WSN to collect data in disaster areas.

AdSIP: Decentralized SIP for Mobile Ad Hoc Networks

SIP signaling protocol relies on centralized SIP servers deployed on the infrastructure of the network to route SIP messages in order to enable user endpoints to discover each other. However, the lack of the infrastructure in ad hoc networks requires that the network nodes support the tasks of participants discovery and SIP messages routing. In this paper, we propose AdSIP protocol which is a completely distributed architecture for SIP that implements SIP servers in selected nodes. The SIP servers are selected using a distributed algorithm constructing a connected minimal global offensive alliance. AdSIP is implemented and compared under NS-2 with TCA protocol which uses a cluster based approach. The simulation results show the advantages of AdSIP and confirm that it is adapted to mobile ad hoc networks by giving low session establishment time, low control overhead and high service availability.

A policy-based context-aware approach for the commitment of mobile transactions

The transaction paradigm ensures consistency in the presence of concurrent accesses to shared data and in the presence of failures. Traditionally, the transaction semantics is defined by the ACID properties (Atomicity, Consistency, Isolation and Durability) which implementation is through such mechanisms as commitment protocols ensuring Atomicity and concurrency control protocols ensuring Isolation. Many transactional models were developed to support the diverse and variable applications needs, and more recently to overcome the constraints induced by the evolution of distributed systems environments toward wireless and mobile. Indeed, the latter are characterized by limitations in computing resources, communications and energy as well as dynamic variations in terms of resource availability and configuration. In this paper, our contribution is mainly focused on the problem of atomic commitment. We adopted an approach based on the context-aware adaptation for the management of mobile transactions. We therefore present the commit protocol aTCP (Adaptable Transaction Commit Protocol) which allows for adaptation to the requirements of applications and mobile context in terms of transactional properties and execution cost. For the implementation of aTCP we offer a context-aware architecture based on policies.

Requirements for an IT based platform for disaster management

The intent of the present work is to identify the main challenges and key requirements towards the provision of an integrated framework that supports decision making and collaboration among multiple actors concerned by disaster management (DM). Also, this work highlights the importance of Information and Communication Technologies (ICT) in this field and proposes an IT-based platform to implement such a framework. The proposed platform offers the main following capabilities: inter-sectorial information sharing, enhancement of public awareness, communication and dissemination of information and enforcement of the regulation control.

LifeTime-aware Backpressure - a new delay-enhanced Backpressure-based routing protocol

Dynamic 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.