269,437 research outputs found

    A Search Strategy of Level-Based Flooding for the Internet of Things

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    This paper deals with the query problem in the Internet of Things (IoT). Flooding is an important query strategy. However, original flooding is prone to cause heavy network loads. To address this problem, we propose a variant of flooding, called Level-Based Flooding (LBF). With LBF, the whole network is divided into several levels according to the distances (i.e., hops) between the sensor nodes and the sink node. The sink node knows the level information of each node. Query packets are broadcast in the network according to the levels of nodes. Upon receiving a query packet, sensor nodes decide how to process it according to the percentage of neighbors that have processed it. When the target node receives the query packet, it sends its data back to the sink node via random walk. We show by extensive simulations that the performance of LBF in terms of cost and latency is much better than that of original flooding, and LBF can be used in IoT of different scales

    Flooding attacks to internet threat monitors (ITM): Modeling and counter measures using botnet and honeypots

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    The Internet Threat Monitoring (ITM),is a globally scoped Internet monitoring system whose goal is to measure, detect, characterize, and track threats such as distribute denial of service(DDoS) attacks and worms. To block the monitoring system in the internet the attackers are targeted the ITM system. In this paper we address flooding attack against ITM system in which the attacker attempt to exhaust the network and ITM's resources, such as network bandwidth, computing power, or operating system data structures by sending the malicious traffic. We propose an information-theoretic frame work that models the flooding attacks using Botnet on ITM. Based on this model we generalize the flooding attacks and propose an effective attack detection using Honeypots

    The Integration of Coastal Flooding into an ArcFLOOD Data Model

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    With the impact of global climate change, the speedy, intelligent and accessible dissemination of coastal flood predictions from a number of modelling tools at a range of temporal and spatial scales becomes increasingly important for policy decision makers. This thesis provides a novel approach to integrate the coastal flood data into an ArcFLOOD data model to improve the analysis, assessment and mitigation of the potential flood risk in coastal zones. This novel methodology has improved the accessibility, dissemination and visualisation of coastal flood risk. The results were condensed into spatial information flows, data model schematic diagrams and XML schema for end-user extension, customisation and spatial analysis. More importantly, software developers with these applications can now develop rich internet applications with little knowledge of numerical flood modelling systems. Specifically, this work has developed a coastal flooding geodatabase based upon the amalgamation, reconditioning and analysis of numerical flood modelling. In this research, a distinct lack of Geographic Information Systems (GIS) data modelling for coastal flooding prediction was identified in the literature. A schema was developed to provide the linkage between numerical flood modelling, flood risk assessment and information technology (IT) by extending the ESRI ArcGIS Marine Data Model (MDM) to include coastal flooding. The results of a linked hybrid hydrodynamic-morphological numerical flood model were used to define the time-series representation of a coastal flood in the schema. The results generated from GIS spatial analyses have improved the interpretation of numerical flood modelling output by effectively mapping the flood risk in the study site, with an improved definition according to the time-series duration of a flood. The improved results include flood water depth at a point and flood water increase which equates to the difference in significant wave height for each time step of coastal flooding. The flood risk mapping provided has indicated the potential risk to infrastructure and property and depicted the failure of flood defence structures. In the wider context, the results have been provided to allow knowledge transfer to a range of coastal flooding end-users.Natural Environment Research Counci

    Neighbourhood-aware counter-based broadcast scheme for wireless ad hoc networks

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    Broadcasting is a vital operation in mobile ad hoc networks (MANETs) and it is crucial to enhance its efficiency to ensure successful deployment. Although flooding is ideal for broadcast operations due to its simplicity and high reachability it suffers from high packet collision which can degrade network performance severely. Counter-based broadcast schemes have been introduced to alleviate the limitations of flooding. This study introduces an enhancement to counter-based broadcast by adjusting the threshold value and the Random Assessment Delay (RAD) using minimal neighbourhood information

    Design and comparative analysis of single-path and epidemic approaches to information and energy management in wireless sensor networks

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    Intelligent energy management is a key challenge in Wireless Sensor Networks. The choice of an appropriate routing algorithm constitutes a critical factor, especially in unstructured networks where, due to their dynamic nature, a reactive routing protocol is necessary. Such networks often favour packet flooding to fulfil this need. One such algorithm is IDEALS, a technique proposed in the literature, which balances energy consumed with information delivered. This paper evaluates the use of a single-path solution with IDEALS to increase efficiency. Simulation results comparing the two approaches show that the single-path algorithm outperforms flooding in terms of energy consumption for any network size. Furthermore the benefit of IDEALS is preserved as its combination with the single-path algorithm maximises information throughput

    (WP 2005-05) Assessing the Determinants of Willingness to Pay for Urban Flood Control: The Role of Locational, Demographic and Attitudinal Factors

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    The urbanization of urban watersheds can influence flooding risks. Traditional Federal Emergency Management Agency (FEMA) flood risk maps identify 100 year floodplains. These maps are updated infrequently. However, as a community urbanizes, flood risks can change, especially for downstream residents. Thus, one would expect that the willingness to pay (WTP) to prevent the worsening of flooding risk would depend in part on the location of the household in the community and their associated flooding risk. Economists and regional scientists have evaluated the role played by traditional demographic factors. However, attitudinal factors measuring community norms, political philosophy, and other psychological factors that may be unique to the individual have not received the same level of scrutiny. Milwaukee, WI has experienced major flooding events, classified as floods with an expected frequency of once every 100 years or less, in 1986 and most recently in 1997 and 1998. In this study, 1000 residents of the Menomonee watershed in Milwaukee were interviewed in a two-wave panel survey (i.e., telephone interviews took place in 2000 and 2001) to determine their willingness to pay for a referendum which would prevent flood risks from worsening. The interviews queried respondents about their attitudes concerning flooding and ecological risks, political beliefs, information seeking behavior, and other psychological factors unique to the respondent. Information was also gathered on demographic characteristics of the respondent, and also that individuals address. The address was geocoded and hydrologic modeling was used to determine the unique flood risk associated with the residence. A willingness to pay function was estimated using Tobit analysis. Preliminary findings indicated that all three categories of factors influence willingness to pay, with psychological factors and flood risk factors having a relatively strong impact on willingness to pay

    Municipal Options to Address Nuisance Flooding of Coastal Highways in Rhode Island

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    Sea level rise and more powerful storm surges and erosion have increased flooding in low-lying coastal areas of Rhode Island. These impacts affect coastal highways, requiring municipalities to make difficult choices about whether and how to maintain or abandon their infrastructure. This fact sheet helps cities and towns understand their legal duties, options, and potential liabilities when considering the future of threatened coastal infrastructure. By using the information in this fact sheet, municipalities can make informed decisions about the consequences of their infrastructure investments. After providing background on nuisance flooding associated with sea level rise, this fact sheet describes Rhode Island law governing responsibility for maintaining public roads. It then describes law and policy considerations related to the two primary options for addressing highway flooding in the state: elevation and abandonment. Considering the legal issues associated with each of these strategies can help municipalities decide the appropriate course of action in the context of a particular location

    To NACK or not to NACK? Negative Acknowledgments in Information-Centric Networking

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    Information-Centric Networking (ICN) is an internetworking paradigm that offers an alternative to the current IP\nobreakdash-based Internet architecture. ICN's most distinguishing feature is its emphasis on information (content) instead of communication endpoints. One important open issue in ICN is whether negative acknowledgments (NACKs) at the network layer are useful for notifying downstream nodes about forwarding failures, or requests for incorrect or non-existent information. In benign settings, NACKs are beneficial for ICN architectures, such as CCNx and NDN, since they flush state in routers and notify consumers. In terms of security, NACKs seem useful as they can help mitigating so-called Interest Flooding attacks. However, as we show in this paper, network-layer NACKs also have some unpleasant security implications. We consider several types of NACKs and discuss their security design requirements and implications. We also demonstrate that providing secure NACKs triggers the threat of producer-bound flooding attacks. Although we discuss some potential countermeasures to these attacks, the main conclusion of this paper is that network-layer NACKs are best avoided, at least for security reasons.Comment: 10 pages, 7 figure
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