2,514 research outputs found

    Managing the Mobility of a Mobile Sensor Network Using Network Dynamics

    Full text link

    DMP: Detouring Using Multiple Paths against Jamming Attack for Ubiquitous Networking System

    Get PDF
    To successfully realize the ubiquitous network environment including home automation or industrial control systems, it is important to be able to resist a jamming attack. This has recently been considered as an extremely threatening attack because it can collapse the entire network, despite the existence of basic security protocols such as encryption and authentication. In this paper, we present a method of jamming attack tolerant routing using multiple paths based on zones. The proposed scheme divides the network into zones, and manages the candidate forward nodes of neighbor zones. After detecting an attack, detour nodes decide zones for rerouting, and detour packets destined for victim nodes through forward nodes in the decided zones. Simulation results show that our scheme increases the PDR (Packet Delivery Ratio) and decreases the delay significantly in comparison with rerouting by a general routing protocol on sensor networks, AODV (Ad hoc On Demand Distance Vector), and a conventional JAM (Jammed Area Mapping) service with one reroute

    Virtual pedagogical model: development scenarios

    Get PDF
    info:eu-repo/semantics/publishedVersio

    Enabling Self-healing Smart Grid Through Jamming Resilient Local Controller Switching

    Get PDF
    A key component of a smart grid is its ability to collect useful information from a power grid for enabling control centers to estimate the current states of the power grid. Such information can be delivered to the control centers via wireless or wired networks. It is envisioned that wireless technology will be widely used for local-area communication subsystems in the smart grid (e.g., in distribution networks). However, various attacks with serious impact can be launched in wireless networks such as channel jamming attacks and denial-of-service attacks. In particular, jamming attacks can cause significant damages to power grids, e.g., delayed delivery of time-critical messages can prevent control centers from properly controlling the outputs of generators to match load demands. In this paper, a communication subsystem with enhanced self-healing capability in the presence of jamming is designed via intelligent local controller switching while integrating a retransmission mechanism. The proposed framework allows sufficient readings from smart meters to be continuously collected by various local controllers to estimate the states of a power grid under various attack scenarios. The jamming probability is also analyzed considering the impact of jammer power and shadowing effects. In addition, guidelines on optimal placement of local controllers to ensure effective switching of smart meters under jamming are provided. Via theoretical, experimental and simulation studies, it is demonstrated that our proposed system is effective in maintaining communications between smart meters and local controllers even when multiple jammers are present in the network

    Secure Connectivity Through Key Predistribution Under Jamming Attacks In Ad Hoc and Sensor Networks

    Get PDF
    Wireless ad hoc and sensor networks have received attention from research communities over the last several years. The ability to operate without a fixed infrastructure is suitable for a wide range of applications which in many cases require protection from security attacks. One of the first steps to provide security is to distribute cryptographic keys among nodes for bootstrapping security. The unique characteristics of ad hoc networks create a challenge in distributing keys among limited resource devices. In this dissertation we study the impact on secure connectivity achieved through key pre-distribution, of jamming attacks which form one of the easiest but efficient means for disruption of network connectivity. In response to jamming, networks can undertake different coping strategies (e.g., using power adaptation, spatial retreats, and directional antennas). Such coping techniques have impact in terms of the changing the initial secure connectivity created by secure links through key predistribution. The objective is to explore how whether predistribution techniques are robust enough for ad hoc/sensor networks that employ various techniques to cope with jamming attacks by taking into account challenges that arise with key predistribution when strategies for coping with jamming attacks are employed. In the first part of this dissertation we propose a hybrid key predistribution scheme that supports ad hoc/sensor networks that use mobility to cope with jamming attacks. In the presence of jamming attacks, this hybrid scheme provides high key connectivity while reducing the number of isolated nodes (after coping with jamming using spatial retreats). The hybrid scheme is a combination of random key predistribution and deployment-based key predistribution schemes that have complementary useful features for secure connectivity. In the second part we study performance of these key predistribution schemes under other jamming coping techniques namely power adaptation and directional antennas. We show that the combination of the hybrid key predistribution and coping techniques can help networks in maintaining secure connectivity even under jamming attacks

    Managed retreats by whom and how? Identifying and delineating governance modalities

    Get PDF
    Managed retreat has become a compelling policy imperative as climate change exacerbates socio-natural hazard risks and imminent harm looms for exposed communities. Retreats may be initiated over different times and scales using various instruments by actors, from the state to the private sector and civil society. However, in the absence of a coherent strategic vision, guiding frameworks, and capacity to manage retreats, at-risk communities, their elected representatives, policy makers, and planners are compelled to embark on retreat governance experiments. Consequently, retreat is perceived as a ‘high regrets’ policy imperative with potentially adverse impacts for community wellbeing, as well as political and professional risks. To help translate managed retreat rhetoric into reality, this paper presents a governance framework that acknowledges the multiplicity of ‘managed retreats.’ Using examples from Aotearoa-New Zealand, we identify and delineate retreat modalities and clarify terminology, converging our framework with the international mobility literature to harness the valuable lessons from decades of human mobility practice
    corecore