Showing papers by "Christian Bonnet published in 2009"

Mobility models for vehicular ad hoc networks: a survey and taxonomy

Abstract: Vehicular Ad-hoc Networks (VANETs) have been recently attracting an increasing attention from both research and industry communities. One of the challenges posed by the study of VANETs is the definition of a vehicular mobility model providing an accurate and realistic vehicular mobility description at both macroscopic and microscopic levels. Another challenge is to be able to dynamically alter this vehicular mobility as a consequence of the vehicular communication protocols. Many mobility models have been developed by the community in order to solve these two issues. However, due to the large number of available models claiming to be adapted to vehicular traffic, and also due to their different and somehow incomparable features, understanding their true characteristics, their degree of realism with respect to vehicular mobility, and real capabilities is a hard task. In this survey, we first introduce a framework that proposes a guideline for the generation of vehicular mobility models. Then, we illustrate the different approaches chosen by the community for the development of vehicular mobility models and their interactions with network simulators. Finally, we propose an overview and taxonomy of a large range of mobility models available for vehicular ad hoc networks. The objective is to provide readers with a guideline to easily understand and objectively compare the different models, and eventually identify the one required for their needs.

Kinetic Multipoint Relaying: Improvements Using Mobility Predictions

Abstract: Multipoint Relaying (MPR) is a technique to reduce the number of redundant retransmissions while diffusing a broadcast message in the network, where only a subset of nodes are allowed to forward packets. The selection is based on instantaneous nodes' degrees, and is periodically refreshed. We propose in this chapter a novel heuristic to select kinetic multipoint relays based on nodes' overall predicted degree, which is solely updated on a per-event basis. We illustrate that this approach significantly reduces the number of messages needed to operate the protocol, yet with similar broadcast properties that the regular MPR, such as network coverage, number of multipoint relays, or flooding capacity.

Host Identity Protocol and Proxy Mobile IPv6: A Secure Global and Localized Mobility Management Scheme for Multihomed Mobile Nodes

Abstract: The evolution of Internet and its hosts does not match anymore the current Internet architecture, designed when mobility, multihoming and security were not considered, and based on IP addresses with the double role of host's identity and host's topological location. In this paper we propose a secure global and localized mobility management scheme suitable for multihomed Mobile Nodes (MNs) and based on Host Identity Protocol (HIP) and Proxy Mobile IPv6 (PMIPv6). It merges the new identifier/locator split architecture proposed by HIP, especially designed for providing security and multihoming to MNs, with the micro-mobility management scheme of PMIPv6, which has been proposed for unmodified MNs with future Global Mobility Management (GMM) protocols. HIP-PMIPv6 combination has double benefits. On one side, it represents an efficient micro-mobility solution for HIP. On the other side, it provides a GMM scheme for PMIPv6, which supports intertechnology handover and multihoming together with security. The HIP-PMIPv6 scheme has been implemented in a real test-bed and experimental results prove its viability.

Combining mobility and heterogeneous networking for emergency management: a PMIPv6 and HIP-based approach

Abstract: Emergency Management is an important topic for research community worldwide, especially after recent major disasters. The problem of supporting mobility at the disaster site to rescue teams equipped with different heterogeneous access technologies and providing interoperability between different agencies and jurisdictions is still under investigation. In this work we propose to merge the advantages of IPv6 micro-mobility management of Proxy Mobile IPv6 (PMIPv6) with macro-mobility management, security, inter-technology handover and multi-homing features of Host Identity Protocol (HIP). This new approach applied to our proposed ad-hoc satellite and wireless mesh system architecture for emergency mobile communications can improve mobility, security, reliability and interoperability in Emergency Management domain.

Distributed Communication Control Mechanisms for Ad Hoc Networks

Abstract: We considered a single hop ad-hoc network consisting of N source-destination pairs. Each transmitter is endowed with a finite buffer and accepts packets from a Poisson distributed arrival process. The channel is described by a Markov chain. We investigate distributed algorithms for joint admission control, rate and power allocation aiming at maximizing the individual or the global throughput defined as the average information rate successfully received. The decisions are based on the statistical knowledge of the channel and buffer states of the other communication pairs and on the exact knowledge of their own channel and buffer states. The problems are formulated as a cooperative and noncooperative games and reduced to the mathematical framework of the variational inequalities problems. The proposed algorithms provide sizable improvements with respect to straightforward extension of decentralized algorithms for multiple access channels to ad hoc networks.

Topology management for public safety networks

Abstract: Topology management for public safety networks (PSNs) presents some particularities which make it a challenging problem. First, the main concerns for PSNs is rapid deployment and survivability. Second, the network requirements for different disaster scenarios may differ completely. This work describes a flexible distributed algorithm to perform network admission control and topology management for public safety wireless networks using as target architecture the network proposed by the CHORIST project [5]. The proposed algorithm is able, not only to dynamically adapt to different network requirements, but also to create homogeneous clusters, where the number of mobile routers attached to each cluster is roughly the same. The technique successfully creates and maintains the desired topology relying only on a simple and customized cost function.

Low complexity cross-layer design for dense interference networks

Abstract: We considered a dense interference network with a large number (K → ∞) of transmitter-receiver pairs Each transmitter is endowed with a finite buffer and accepts packets from an arrival process Each transmitter-receiver link is a fading vector channel with N diversity paths whose statistics are described by a Markov chain We investigate distributed algorithms for joint admission control, rate and power allocation aiming at maximizing the individual throughput defined as the average information rate successfully received The decisions are based on the statistical knowledge of the channel and buffer states of the other communication pairs and on the exact knowledge of their own channel and buffer states In the case of a finite number of communication pairs this problem is computationally extremely intensive with an exponential complexity in the number of users Assuming that K,N → ∞ with constant ratio the algorithm complexity becomes substantially independent of the number of active communications and grows with the groups of users having distinct asymptotic channel statistics The cross-layer design is investigated for different kind of decoders at the receiver The benefits of a cross layer approach compared to a resource allocation ignoring the states of the queues are assessed The performance loss due to the use of policies designed for asymptotic conditions and applied to networks with a finite number of active communications is studied

Dynamic topology implementation and maintenance for the CHORIST network

Abstract: This paper presents the implementation and evaluation of a distributed topology management algorithm for public safety networks (PSNs) to implement the CHORIST architecture1. Topology management for this kind of network is a mission critical problem, for a mission critical network. PSNs are the networks installed by the authorities to coordinate relief/rescue efforts in case of disasters. The main concerns for PSNs are rapid deployment and survivability. The whole operation and teams coordination schema depends on how well deployed the network was and how stable and reliable the network is during its lifetime. The more stable the network structure is in a rescue operation field the better. The proposed algorithm is able to dynamically adapt to the nodes mobility thus maintaining the desired topology

Evaluation of Scalable Proxy Mobile IPv6 in Wireless Mesh Networks

Abstract: This paper evaluates our work of Scalable Proxy Mobile IPv6 (SPMIPv6) in a Wireless Mesh Network (WMN), which is a promising solution for ubiquitous Internet access and a wide range of applications. The aspects of scalability and signaling cost are evaluated respectively: the scalability is evaluated by numerical analysis while the signaling cost with respect to delay is evaluated by a virtualization-based method. It is shown that the SPMIPv6 extension can scale the network better than the base Proxy Mobile IPv6 (PMIPv6) protocol. The quantitative results are provided to complete our previous qualitative results and to validate the application of SPMIPv6 for WMN.

Vehicular Mobility Simulation with

Abstract: During the last few years, continuous progresses in wireless communications have opened new research fields in computer networking, aimed at extending data networks connectivity to environments where wired solutions are impracticable. Among these, vehicular communication is attracting growing attention from both academia and industry, owing to the amount and importance of the related applications, ranging from road safety to traffic control and up to mobile entertainment. Vehicular Ad-hoc Networks (VANETs) are self-organized networks built up from moving vehicles, and are part of the broader class of Mobile Ad-hoc Networks (MANETs). Owing to their peculiar characteristics, VANETs require the definition of specific networking techniques, whose feasibility and performance are usually tested by means of simulation. One of the main challenges posed by VANETs simulations is the faithful characterization of vehicular mobility at both the macroscopic and microscopic levels, leading to realistic non-uniform distributions of cars and velocity, and unique connectivity dynamics. However, freely distributed tools which are commonly used for academic studies only consider limited vehicular mobility issues, while they pay little or no attention to vehicular traffic generation and its interaction with its motion constraints counterpart. Such a simplistic approach can easily raise doubts on the confidence of derived VANETs simulation results. In this paper we present VanetMobiSim, a freely available generator of realistic vehicular movement traces for networks simulators. The traces generated by VanetMobiSim are validated first by illustrating how the interaction between featured motion constraints and traffic generator models is able to reproduce typical phenomena of vehicular traffic. Then, the traces are formally validated against those obtained by TSIS-CORSIM, a benchmark traffic simulator in transportation research. This makes VanetMobiSim one of the few vehicular mobility simulator fully validated and freely available to the vehicular networks research community.