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Security against routing attacks in MANET is most critical issue and traditional concepts of cryptography, authentication, or Watchdog are not that significant in mitigation of these attacks. In recent years, trust‐based approach provides a reputation system that compose of different components to provide security against routing attacks. In this paper, we provide an in‐depth analysis of various components that are used in trust‐based mechanism and techniques deployed in effective and efficient execution of task by the components. Trust‐based mechanisms generally have five components: monitoring and information gathering, trust calculation and evaluation unit, trust recommendation unit, decision‐making and dissemination of detection unit. All or some of these units cooperate together to provide a reliable communication environment with the aim to prevent routing attacks from participating in route formation process and detect attacking nodes simultaneously. Different routing attacks and measures in trust‐based mechanism along with some published work are discussed to understand the implementation of this type of mechanism. Various related issues are explored, discussed, and recommendations are pointed out for future research work in this field. 相似文献
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Sourabh Bharti Kiran K. Pattanaik 《International Journal of Communication Systems》2016,29(13):2015-2027
Accuracy of sensed data and reliable delivery are the key concerns in addition to several other network‐related issues in wireless sensor networks (WSNs). Early detection of outliers reduces subsequent unwanted transmissions, thus preserving network resources. Recent techniques on outlier detection in WSNs are computationally expensive and based on message exchange. Message exchange‐based techniques incur communication overhead and are less preferred in WSNs. On the other hand, machine learning‐based outlier detection techniques are computationally expensive for resource constraint sensor nodes. The novelty of this paper is that it proposes a simple, non message exchange based, in‐network, real‐time outlier detection algorithm based on Newton's law of gravity. The mechanism is evaluated for its accuracy in detecting outliers, computational cost, and its influence on the network traffic and delay. The outlier detection mechanism resulted in almost 100% detection accuracy. Because the mechanism involves no message exchanges, there is a significant reduction in network traffic, energy consumption and end‐to‐end delay. An extension of the proposed algorithm for transient data sets is proposed, and analytic evaluation justifies that the mechanism is reactive to time series data. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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通过分析位置与身份分离协议中可能存在的映射欺骗所带来的安全隐患,提出了一种缓解映射欺骗威胁的新型映射机制。该机制在映射理论中引入了基于反馈评判的信任度模型,通过对信任度的动态评判,增加了映射信息的可信性。同时,采用自证明标识代表隧道路由器的身份信息,有效地保障了映射信息源的真实性。性能分析和仿真实验表明,该机制为位置与身份分离协议的映射理论提供了良好的安全保障,通过设定不同的信任度门限,能够有效缓解隧道路由器对虚假映射信息的使用,从而进一步降低了映射欺骗的危害。 相似文献
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H. C. Leligou P. Trakadas S. Maniatis P. Karkazis T. Zahariadis 《Wireless Communications and Mobile Computing》2012,12(12):1091-1103
As the applications of wireless sensor networks proliferate, the efficiency in supporting large sensor networks and offering security guarantees becomes an important requirement in the design of the relevant networking protocols. Geographical routing has been proven to efficiently cope with large network dimensions while trust management schemes have been shown to assist in defending against routing attacks. Once trust information is available for all network nodes, the routing decisions can take it into account, i.e. routing can be based on both location and trust attributes. In this paper, we investigate different ways to incorporate trust in location‐based routing schemes and we propose a novel way of balancing trust and location information. Computer simulations show that the proposed routing rule exhibits excellent performance in terms of delivery ratio, latency time and path optimality. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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由于Dempster组合规则所存在的不足,在组合冲突信息时,会得出与直觉相反的结论。针对Zadeh悖论,Haenni给出了反驳,但冲突产生的原因分析不够全面。鉴于此,本文在他们的基础上,总结出冲突产生的原因,它不仅与传感器受干扰有关,与识别框架不完整也有关系,其中识别框架不完整还包括框架中的元素不详尽,出现了新目标和在两两证据进行推理过程中目标丢失导致的潜在冲突。 相似文献
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分析现有几种证据推理规则的不足及其证据冲突敏感性,然后综合证据源可信度和证据支持度等因素,分析了证据集的有效性,改进了合成规则,因合成规则体现了证据集特征,使得冲突证据集合成的结果更趋合理。数值实验结果验证了改进规则的有效性。 相似文献
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This paper presents a model‐based image steganography method based on Watson's visual model. Model‐based steganography assumes a model for cover image statistics. This approach, however, has some weaknesses, including perceptual detectability. We propose to use Watson's visual model to improve perceptual undetectability of model‐based steganography. The proposed method prevents visually perceptible changes during embedding. First, the maximum acceptable change in each discrete cosine transform coefficient is extracted based on Watson's visual model. Then, a model is fitted to a low‐precision histogram of such coefficients and the message bits are encoded to this model. Finally, the encoded message bits are embedded in those coefficients whose maximum possible changes are visually imperceptible. Experimental results show that changes resulting from the proposed method are perceptually undetectable, whereas model‐based steganography retains perceptually detectable changes. This perceptual undetectability is achieved while the perceptual quality — based on the structural similarity measure — and the security — based on two steganalysis methods — do not show any significant changes. 相似文献
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Muhammad Sajid Haroon Ziaul Haq Abbas Fazal Muhammad Ghulam Abbas 《International Journal of Communication Systems》2020,33(10)
In heterogeneous wireless networks, signal‐to‐interference‐plus‐noise ratio (SINR) suffers degradation due to strong interference received by users from offloaded macro base station (mBS). Similarly, cell‐edge users experience low SINR due to their distant locations. Moreover, small base stations (sBSs) located in the vicinity of mBS experience reduced coverage due to the high transmit power of mBS. To overcome these limitations, we use Stienen's model as a base station deployment strategy to improve network performance gain. More specifically, we use reverse frequency allocation (RFA) as an interference management scheme together with Stienen's model to significantly improve SINR, enhance edge user coverage, and avoid sBS deployment near the mBS. In the proposed set‐up, the available coverage region is divided into two noncontiguous regions, ie, center region and outer region. Furthermore, mBSs are uniformly distributed throughout the coverage region using independent Poisson point processes, while sBSs are deployed only in outer region using Poisson hole process (PHP). Closed‐form expressions for coverage probabilities are characterized for the proposed model. Numerical results show that the proposed scheme yields improved SINR with enhanced edge user coverage and requires fewer number of sBSs. 相似文献
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为了更好地促进旅游信息个性化推荐效果的提升,需对用户行为信息进行深度挖掘。文中基于多维数据融合,构建并研究了个性化旅游信息推荐模型。首先,结合用户的历史浏览、检索、点赞及评论数据,分析用户对不同景区的兴趣度。其次,结合用户的旅行次数、旅行时间以及具体的旅行地点信息,分析用户的偏好选择对旅游大数据的影响力。接着,结合用户对景区兴趣度的分析结果,综合计算用户对景区所在地的偏好选择。最后,以地区偏好为范围,将对旅游大数据影响力较高用户的兴趣度TOP-N景区信息作为最终的推荐结果。测试结果表明,归一化折损累计增益 NDCG随着推荐信息数量k的增加呈现出稳定提升的趋势,且相比对比模型,文中提出的模型得到的参数值始终处于较高水平,说明该模型具有可靠的推荐效果。 相似文献
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The latest innovation of the global navigation satellite systems (GNSS) technologies plays an important role in improving the quality and safety of modern life. Most of the applications evolved from the integration between GNSS, geographical information systems (GIS) and wireless communications and networking (WCN) systems. The wide spread applications that are using these technologies include: the automatic vehicle location (AVL), tracking systems, navigation systems, pedestrian navigation systems, intelligent transportation systems, precise positioning, and emergency callers, among others. The location‐based services (LBS) are possible only by the combination of GNSS, GIS and WCN. The growing need for commercial LBS has forced cellular‐phone and network manufacturers to concentrate on positioning solutions, which are even more precise than the regulatory mandates for positioning of emergency callers and other user services and applications. In this paper, we will present a literature review of the GNSS, the three satellite systems GPS, GLONASS and Galileo, which are aimed to support GNSS services, and a comparison between them and their role in creating a GIS. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Jie Zhou Hao Jiang Hisakazu Kikuchi 《International Journal of Communication Systems》2016,29(3):459-477
To test an adaptive array algorithm in cellular communications, we developed a geometry‐based statistical channel model for radio propagation environments, which provides the statistics of the angle of arrival and time of arrival of the multipath components. This channel model assumes that each multipath component of the propagating signal undergoes only one bounce traveling from the transmitter to the receiver and that scattering objects are located according to Gaussian and exponential spatial distributions, and a new scatterer distribution is proposed as a trade‐off between the outdoor and the indoor propagation environments. Using the channel model, we analyze the effects of directional antennas at the base station on the Doppler spectrum of a mobile station due to its motion and the performance of its MIMO systems. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献