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基于簇的无线传感器网络入侵检测系统 总被引:1,自引:1,他引:1
基于无线传感器网络的分簇结构,运用Agent技术设计了一个入侵检测系统.在网络中的每个节点部署IDS代理,其中包括本地检测Agent和全局检测Agent两个不同代理,分别完成不同的检测任务.提出采用蓝牙通信技术,引用蓝牙散射网形成算法TPSF构建传感器网络的簇节点层,完成簇的划分,进而对不同的Agent进行任务分配.通过限制节点的角色对算法进行改进,减轻节点的复杂度,从而使IDS代理能有效地工作,提高节点的安全系数. 相似文献
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Sudhanshu Tyagi Sudeep Tanwar Sumit Kumar Gupta Neeraj Kumar Joel J.P.C.Rodrigues 《中兴通讯技术(英文版)》2014,(3):22-29
Over the past few decades, there has been a revolution in ICT, and this has led to the evolution of wireless sensor networks(WSN), in particular, wireless body area networks. Such networks comprise a specialized collection of sensor nodes(SNs) that may be deployed randomly in a body area network to collect data from the human body. In a health monitoring system, it may be essential to maintain constant environmental conditions within a specific area in the hospital. In this paper, we propose a temperature-monitoring system and describe a case study of a health-monitoring system for patents critically ill with the same disease and in the same environment. We propose Enhanced LEACH Selective Cluster(E-LEACH-SC) routing protocol for monitoring the temperature of an area in a hospital. We modified existing Selective Cluster LEACH protocol by using a fixed-distance-based threshold to divide the coverage region in two subregions. Direct data transmission and selective cluster-based data transmission approaches were used to provide short-range and long-distance coverage for the collection of data from the body of ill patients. Extensive simulations were run by varying the ratio of node densities of the two subregions in the health-monitoring system. Last Node Alive(LNA), which is a measure of network lifespan, was the parameter for evaluating the performance of the proposed scheme. The simulation results show that the proposed scheme significantly increases network lifespan compared with traditional LEACH and LEACH-SC protocols, which by themselves improve the overall performance of the health-monitoring system. 相似文献
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为了适应超大规模集成电路自动版图设计的需要,本文提出以改进的群法为基础的宏单元门阵列布局方法,它通过同时考虑单元主单元连接度进行结群,并结合广义力向量松弛法,具有速度快,迭代改善效果明显等特点,本文最后给出实验例子,验证了算法的有效性。 相似文献
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In a Mobile Ad hoc Network (MANET), after a mobile node is configured with a unique IP address it can perform the unicast communications. In order to reduce the address configuration cost and shorten the latency, this paper proposes an IPv6 address configuration scheme for a MANET. In the scheme, the cluster-based architecture is proposed. In the architecture, the clustering mechanism is combined with the address configuration process in order to achieve the low-cost and low-latency address configuration for all nodes in a MANET. Based on the architecture, the distributed address configuration algorithm is proposed. In the algorithm, a cluster member acquires an address from a cluster head within one-hop scope, so the address configuration task is distributed around cluster heads. In this way, the address configuration in different clusters can be performed in parallel, so the address configuration delay is shortened and the network scalability is improved. The address reclamation/maintenance algorithm is also proposed so that the address resources released by failed nodes can be rapidly recovered for reuse. Finally, the merging/splitting algorithm is proposed in order to ensure that no address collision happens in a MANET. This paper analyzes the performance parameters of the proposed scheme, and the data results show that the proposed scheme effectively reduces the address configuration cost and shortens the delay. 相似文献
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论文提出了一种基于分簇结构的无线传感器网络时间同步算法.在分簇网络结构中,参考DMTS,仿照TPSN采用在MAC层给控制帧标记时同戳的方式,实现了传感器节点的能量效率,进一步提高了时间同步精度.分析表明.本算法在精度和能耗上都有所改进. 相似文献
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Massive machine type communication aims to support the connection of massive devices,which is still an important scenario in 6G. In this paper, a novel cluster-based massive access method is proposed for massive multiple input multiple output systems. By exploiting the angular domain characteristics, devices are separated into multiple clusters with a learned cluster-specific dictionary, which enhances the identification of active devices. For detected active devices whose data recovery fails, p... 相似文献
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IP address autoconfiguration of mobile nodes is highly desirable in the practical usage of most mobile ad hoc networks (MANETs).
This paper proposes cluster-based autoconfiguration, a novel approach for the efficient address autoconfiguration of MANETs.
The cluster structure derived from clustering techniques is used to manage address assignment and conflict resolution. By
introducing the concept of virtual address agents (AAs), the proposed approach can be applicable to many existing clustering
protocols. Finally, analysis and simulation demonstrate that the proposed scheme outperforms the previous autoconfiguration
approaches.
相似文献
Longjiang LiEmail: |
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Stewart C. Kai Shen Dwarkadas S. Scott M.L. Jian Yin 《Distributed Systems Online, IEEE》2004,5(10):1-1
The growth of the Internet and of various intranets has spawned a wealth of online services, most of which are implemented on local-area clusters using remote invocation (for example, remote procedure call/remote method invocation) among manually placed application components. Component placement can be a significant challenge for large-scale services, particularly when application resource needs are workload dependent. Automatic component placement has the potential to maximize overall system throughput. The key idea is to construct (offline) a mapping between input workload and individual-component resource consumption. Such mappings, called component profiles, then support high-performance placement. Preliminary results on an online auction benchmark based on J2EE (Java 2 Platform, Enterprise Edition) suggest that profile-driven tools can identify placements that achieve near-optimal overall throughput. 相似文献
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高光谱数据的有效压缩成为遥感技术发展中需要迫切解决的问题.提出了一种基于分类非线性预测的高光谱图像无损压缩算法.针对不同频谱波段间相关性不同的特点,根据相邻波段相关性大小进行波段分组.为提高谱间预测性能,对各组波段进行最优排序.采用自适应波段选择算法对高光谱图像进行降维,并利用k-means算法对降维后波段的谱向矢量进行分类.在参考波段和预测波段中选取具有相同空间位置的上下文结构,在分类结果的基础上,对当前波段进行谱间非线性预测.参考波段采用JPEG-LS标准进行压缩,预测残差进行Golomb-Rice编码.对AVIRIS型高光谱图像的实验结果表明,该算法可显著降低压缩后的平均比特率. 相似文献
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在基于分簇架构的水下传感器网络(Underwater Sensor Networks ,UWSNs)中,当簇首以单跳或多跳的通信方式将数据传输至Sink节点时,由于簇首转发大量数据而负载过重,会过早耗尽能量而死亡,这将导致提前出现对监测区域的覆盖盲区。以改善覆盖效果为目标的LEACH-Coverage-U算法由于选举簇首的分簇方法具有随机性,也无法很好解决该问题。本文提出了一种水下传感器网络单跳覆盖保持路由算法(Single-hop Coverage-Preserving Routing Algo-rithm ,SCPR),首先定义了覆盖冗余度(Coverage Redundancy ,CR),然后根据该度量来选举簇首,最终以单跳方式直接将数据传送至Sink节点。为减少簇首能耗并获得更高的网络覆盖率,本文还提出一种多跳覆盖保持路由算法(Multi-hop Coverage-Preserving Routing Algorithm ,MCPR ),簇首之间通信时优先考虑父节点中CR较高的簇首作为其下一跳路由,以多跳路由将数据传送至Sink节点。仿真结果表明,与LEACH-Coverage-U算法相比,SCPR、MCPR算法避免了其选举簇首时的随机性,提高了网络覆盖率,降低了网络能耗,延长了网络生命周期。 相似文献
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Dazhi Piao 《Wireless Personal Communications》2014,74(2):891-908
The information-theoretic capacity for the cluster-based multicell cooperative processing (MCP) network with inter-cluster interference is investigated in this paper. An upper bound for the ergodic capacity is derived by the QR decomposition of the channel matrix, which is concisely expressed and close to the results from numerical simulations. Capacity results for the universal frequency reuse (UFR) network show that the cluster-based MCP system has great advantages over the non-cooperated system, and the capacity gain depends mainly on the size of the cooperative cluster, the radius of the cell and the path loss exponent (PLE). However, the cluster-based UFR system is still interference limited, whose capacity declines sharply due to the inter-cluster interference. Therefore, a cluster-based fractional frequency reuse (FFR) network is proposed to improve the system capacity, simulation results show that the cluster-based FFR system can outperform the UFR system, especially for the cases of small radius of cell or small PLE. 相似文献
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基于分簇的Ad hoc网络分布式认证方案 总被引:1,自引:0,他引:1
认证是保证Ad hoc网络通信安全的重要技术。该文针对分布式认证方案分别运用在平面Ad hoc网络和分簇结构中的优缺点进行了比较研究,提出了一种区域认证方案,该方案采用分簇结构,将Ad hoc网络分割为相互独立的认证区域,既减少了网络开销,又增强了认证服务效率,且安全性和可扩展性较好,适用于大规模Ad hoc网络。 相似文献
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本文提出了一种基于分簇结构的无线传感器网络MAC协议.在基于层次式路由协议的分簇网络结构中,通过综合基于竞争和基于时分复用协议的优缺点,将时间划分为交替的随机访问和调度访问两个阶段,在随机访问阶段簇内节点采用CSMA/CA实现无线信道共享.在调度访问阶段,节点根据簇首分配的时隙实现数据无冲突通信.在簇与簇之间采用FDMA避免信道干扰实现网络的扩展.分析和仿真结果表明本协议在能量效率、时间同步和网络扩展上都有所改进. 相似文献
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A wireless sensor network (WSN) consists of spatially distributed autonomous devices which use sensor nodes to monitor physical or environmental conditions cooperatively. Currently, WSNs are expected to be integrated into the internet of things (IoT), where sensor nodes join the internet dynamically and collaborate to accomplish their tasks. In the application of the IoT, WSNs can play an important role by collecting surrounding contextual and environmental information. However, ensuring a stable and reliable topology is an important issue with regard to WSNs. To cope with the influence of faulty components, it is essential to reach a common agreement in the presence of faults, before performing certain tasks. However, the Byzantine agreement (BA) problem is a fundamental issue in fault-tolerant distributed systems. To enhance the fault tolerance and reliability of the WSN, the BA problem in the cluster-based WSN (CWSN) is revisited in this study. The proposed protocol can achieve agreement on a common value among all functional nodes in a minimal number of message exchange rounds, and can tolerate a maximal number of allowable faulty components in the CWSN. 相似文献
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The cognitive radio (CR) technology is an efficient approach to share the spectrum. But how to access the idle channels effectively is a challenging problem. To solve this problem, we propose a MAC protocol for cluster-based CR ad hoc networks, with the aim of making cluster structure more robust to the primary users’ channel re-occupancy activities, so that the CR users can use the idle spectrum more efficiently. Under this framework, a cluster formation algorithm based on available channels, geographical position and experienced statistics is proposed to maximize the network throughput and maintain the cluster topology stability. The schemes for new CR user joining a cluster and cluster maintenance are also designed. An experience database is proposed to store the experienced statistics which are obtained from spectrum occupancy history. Such a database can be used to support the acts of nodes, such as neighbor discovery and cluster forming. Simulation results reveal that our proposed framework not only outperforms conventional CR MAC protocols in terms of throughput and packet delay, but also generates a smaller number of clusters and has more stable cluster structure with less reclustering time. 相似文献
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In recent years,several random key pre-distribution schemes have been proposed to bootstrap keys for encryption,but the problem of key and node revocation has received relatively little attention.In this paper,based on a random key pre-distribution scheme using clustering,we present a novel random key revoca-tion protocol,which is suitable for large scale networks greatly and removes compromised information efficiently.The revocation protocol can guarantee network security by using less memory consumption and communication load,and combined by centralized and distributed revoca-tion,having virtues of timeliness and veracity for revoca-tion at the same time. 相似文献