About the Self-Stabilization of a Virtual Topology for Self-Organization in Ad Hoc Networks

International audienceAd hoc networks are spontaneous wireless networks without any wired infrastructure, composed of mobile terminals. We assume that nodes must collaborate to set up an efficient network, such a collaboration requiring a self-organization in the network. We proposed a virtual structure to organize the network: the backbone is a connected structure helping to optimize the control traffic flooding. Clusters form services area, hierarchizing the network, electing one leader per cluster. Since the ad hoc topology is volatile, the self-stabilization of the algorithms is vital. The algorithms for both the construction and the maintenance are analytically studied to prove the self-stabilization of the proposed self-organization. Thus, the virtual structure is efficient and very scalable, a local topology change impacting only locally the virtual structure. Finally , simulations investigate the behavior and the performances of the virtual structure

Application de Concepts de Routage Géographique au Routage par Gradient: une Étude Qualitative

Poster à l'occasion du colloque CFIP : 4 pagesLes réseaux de capteurs sans fil connaissent un fort engouement ces dernières années, à la fois dans le monde académique et dans le monde industriel, grâce notamment, au grand nombre d'applications envisagées, et à l'apparition de solutions commerciales viables. A cause de leurs contraintes propres, des mécanismes de routage spécifiques ont été proposés. Le routage géographique et le routage par gradient sont des candidats intéressants pour les réseaux de capteurs, puisqu'ils ne requièrent qu'une phase d'auto-organisation minimale. Dans cet article, nous montrons que les concepts du routage géographique sont applicables au routage par gradient. Nous mettons en évidence une faille dans la règle de la main droite, et nous proposons une solution sous la forme d'un protocole appliqué au routage géographique et par gradient

On the Performances of the Routing Protocols in MANET: : Classical versus Self-Organized Approaches

International audienceMobile Ad Hoc Networks (MANET) are spontaneous wireless networks of mobile nodes without any fixed infrastructure. MANET are promised to a large spectrum of military or civilian utilizations. Routing is a key topic in such networks: overhead must be minimized, optimizing the delay and reducing the packet losses. Several routing protocols were proposed in the literature but, recently, new routing protocols based on a self-organization, like Virtual Structure Routing (VSR), were proposed. VSR is based on a self-organized structure with an important stability and persistence. In this paper, we aim to quantify the contribution of the self-organization on the routing behavior and performances. We oppose VSR as a self-organized protocol to the classical one: reactive (AODV), proactive (OLSR) and clustered (CBRP). The impact of the mobility and the density, the horizontal and the vertical scalabilities are studied

A self-organization structure for Hybrid Networks

International audienceThis paper focuses on the self-organization of ad hoc and hybrid networks. We propose to organize networks with two integrated virtual structures: a backbone and clusters. The backbone helps to optimize the flooding of control packets, and to offer a natural prolongation of the backbone of wired networks. Clusters help to hierarchize the network, each of which is managed logically by its clusterhead. Since MANETs are mobile, we propose distributed algorithms for both the construction and the maintenance to preserve an efficient virtual structure despite topology changes. Simulations results exhibit the robustness and persistence of the proposed virtual structure