共查询到20条相似文献,搜索用时 99 毫秒
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能够支持负载均衡的ID分配方法是实现与维护DHT overlay的基础,已有常数度DHT多采用纯集中式或纯分布式方法,不能很好地解决拓扑信息维护开销与拓扑平衡程度这一矛盾.针对这一不足,在分析拓扑中通用树结构的基础上,本文提出了基于内在结构Routing Forest的ID分配方法RFIDAM,通过规律性地聚合局部平衡信息来指导新节点的加入以实现拓扑平衡.实验表明,通过引入少量维护与路由开销,该方法使得拓扑达到节点ID长度差小于2的最优平衡目标. 相似文献
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对Burmester等人提出的非认证组密钥协商协议的安全性进行了深入分析,指出该协议不能抵抗内部恶意节点发起的密钥协商阻断攻击和密钥控制攻击.提出了一种故障容忍的组密钥协商(FT-GKA)协议,FT-GKA协议在密钥协商过程中加入了消息正确性的认证机制,该机制利用数字签名技术检测组内恶意节点,并在驱逐恶意节点后保证组内诚实节点能计算出正确的会话密钥,解决了Burmester等人提出协议中存在的内部恶意节点攻击问题.并证明提出的协议在DDH假设下能抵抗敌手的被动攻击,在DL假设和随机预言模型下能够抵抗内部恶意节点发起的密钥协商阻断攻击和密钥控制攻击.理论分析与实验测试表明,提出的协议具有较高的通信轮效率和较低的计算开销. 相似文献
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该文针对无线传感器网络节点处理能力、存储能力和能量供应均有限的特点,提出一种基于移动Agent的JPEG2000分布式编码算法.采用多个节点对图像进行分布式编码,通过引入移动Agent机制来实现网络节点间的信息交互,在保证图像编码性能不变的情况下,降低单个节点能耗,使系统不因单个节点能量耗尽而瘫痪,以延长系统的生命周期.仿真实验结果表明,该文所提出的基于移动Agent的分布式编码算法在无线传感器网络环境中可以保证编码后的图像质量没有下降,并能有效均衡系统能耗、延长网络工作寿命达3倍左右. 相似文献
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无线传感器网络的分布式能量有效非均匀成簇算法 总被引:4,自引:0,他引:4
研究了现有成簇路由算法,提出了分布式能量有效成簇路由算法,该算法主要包括3部分内容:一是选择候选簇头时通过引入平均能量因子来平衡全网节点的剩余能量情况;二是构造了基于能量和距离的能量消耗率函数以平衡节点的能量效率;三是首次提出了基于同构单跳网络的分布式能量有效非均匀成簇路由算法.理论和仿真结果均说明该算法优于EECS,生命周期比EECS延长达到约30%. 相似文献
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无线传感器网络中的分布式Voronoi覆盖控制算法 总被引:1,自引:0,他引:1
以覆盖部分目标区域的传感器网络为研究背景,在通信半径不小于2倍传感半径的条件下,提出了一种维持网络原有覆盖范围、连通性的分布式Voronoi覆盖控制算法.首先,提出了一种基于局部Voronoi区域的冗余识别规则,其计算复杂度与节点密度无关;然后,提出了一种能量优先的Voronoi调度规则,通信相邻、局部Voronoi不相邻的节点可以同步执行冗余识别,提高分布式调度的收敛性.仿真实验表明,所提算法求解活跃节点的数量、平均覆盖度与集中式算法接近,优于一般的分布式算法,而在活跃节点的平均能量、算法性能等方面更加具有优势. 相似文献
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在无线传感器网络(WSNs)中,节点复制攻击和女巫攻击可扰乱数据融合和阈值选举等网络操作.发起这两种攻击需先通过邻居发现认证过程.考虑到在WSNs中发起邻居认证是不频繁的,提出了一种基于单向密钥链的ID认证防御机制(OKCIDA),降低攻击者在任何时间段发起这两种攻击的可能性.然后基于椭圆曲线离散对数问题,构造对称参数,并组合OKCIDA和利用节点邻居关系,提出了一种无需位置的邻居认证协议(LFNA),以阻止复制节点和女巫节点成功加入网络.最后给出了安全性证明和分析,并在安全和开销方面将LFNA与已有典型防御方案进行了比较,结果表明该方案具有一定的优势. 相似文献
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该文针对多源-多中继放大转发协作通信网络,以最小化系统总功率为目标,在保证系统满足一定中断概率的前提下,提出了一种分布式功率分配与中继选择算法.算法由源节点自主选择为其转发信息的中继节点,并引入定时器,通过竞争方式避免了分布式所导致的中继选择冲突.中继收到来自源节点的信号后,只需根据转发门限自主判断是否进行转发,从而完成传输.仿真结果表明该分布式算法能够有效降低传输所需要的总发射功率.并且与集中式控制所获得的最优中继选择与功率分配算法相比性能相近,但所提分布式算法显著降低了系统的控制开销. 相似文献
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频谱感知是认知无线电领域的关键技术.在协作频谱感知中,分布式一致性加权算法检测性能较好但收敛速度慢.该文引入身份代码概念,用以区分各次用户的状态值和权值,避免节点间数据的重复融合,并提出了一种快速分布式加权协作频谱感知算法.仿真结果表明,所提算法检测性能与分布式一致性加权算法相当,同时收敛速度明显提升. 相似文献
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Ubarhande Sachin D. Doye Dharmpal D. Nalwade Prakash S. 《Wireless Personal Communications》2017,97(2):2087-2096
Mobile ad hoc network is open medium, infrastructure-less and easy to install. Despite these features, mobile ad hoc network is vulnerable to various security attacks. Black hole and gray hole security attacks outrank among all security attacks. This paper proposes a distributed delegation-based scheme, namely, a secure path selection scheme. The proposed scheme identifies and allows only trusted nodes to become part of active path. The simulation results revealed that proposed scheme improved the packet delivery ratio, packet loss rate, throughput by 8% and routing overhead by 5% as compared to other system.
相似文献12.
Cognitive Wireless Mesh Networks (CWMN) is a novel wireless network which combines the advantage of Cognitive Radio (CR) and
wireless mesh networks. CWMN can realize seamless integration of heterogeneous wireless networks and achieve better radio
resource utilization. However, it is particularly vulnerable due to its features of open medium, dynamic spectrum, dynamic
topology, and multi-top routing, etc.. Being a dynamic positive security strategy, intrusion detection can provide powerful safeguard to CWMN. In this paper, we
introduce trust mechanism into CWMN with intrusion detection and present a trust establishment model based on intrusion detection.
Node trust degree and the trust degree of data transmission channels between nodes are defined and an algorithm of calculating
trust degree is given based on distributed detection of attack to networks. A channel assignment and routing scheme is proposed,
in which selects the trusted nodes and allocates data channel with high trust degree for the transmission between neighbor
nodes to establish a trusted route. Simulation results indicate that the scheme can vary channel allocation and routing dynamically
according to network security state so as to avoid suspect nodes and unsafe channels, and improve the packet safe delivery
fraction effectively. 相似文献
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公钥证书是公开密钥的重要载体。随着以Ad Hoc为代表的自组织网络、分布式网络的发展,需要安全的可对公钥证书的生成、发布、更新、验证、撤销等实现自治管理的自组织证书管理方案。论文提出了一种安全的证书自组织管理方案,该方案利用单向哈希链,实现了无在线可信第三方的证书自组织管理。该方案的安全性同时依赖于节点私钥与单项哈希链的安全,具有更好的安全特性。 相似文献
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移动Ad-hoc网络(MANETs)具有开放的媒质,动态的拓扑结构,分布式的合作和受限的网络能力等基本特点。网络中移动节点具有匿名性和高度自治的特点,网络通讯依靠在通信路径上的中间节点转发数据包,实现无线传输范围外节点间的正常通信。该文提出了一种独特的MANETs中基于频率下多目标可信路由决策算法,它和现在大多数路由算法都是在时间域下使用单一约束参数选择路由的方式截然不同。利用概率理论分析安全和可信路由,基于概率密度函数的时频相互转化,减小计算复杂度,解决MEANTs中节点间缺乏物理安全以及在低信任水平和节点相互勾结扰乱网络操作情况下,发现可信安全路由难的问题。实例分析证明了此算法的可行性。 相似文献
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Time-stamping is a technique used to prove the existence of a digital document prior to a specific point in time. Today, implemented schemes rely on a centralized server model that has to be trusted. We point out the drawbacks of these schemes, showing that the unique serveur represent a weak point for the system. We propose an alternative scheme which is based on a network of servers managed by administratively independent entities. This scheme appears to be a trusted and reliable distributed time-stamping scheme. 相似文献
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Since Vehicular ad hoc networks (VANETs) are vulnerable to various kinds of attacks, there is a need to fulfill the security requirements like message privacy, integrity, and authentication. The authentication technique is said to be efficient if it detects compromised nodes accurately with less complexity, reduced authentication delay, and keying overhead. In this paper, a trust-based authentication scheme for cluster-based VANETs is proposed. The vehicles are clustered, and the trust degree of each node is estimated. The trust degree is a combination of direct trust degree and indirect trust degree. Based on this estimated trust degree, cluster heads are selected. Then, each vehicle is monitored by a set of verifiers, and the messages are digitally signed by the sender and encrypted using a public/ private key as distributed by a trusted authority and decrypted by the destination. This verifies the identity of sender as well as receiver thus providing authentication to the scheme. By simulation results, we prove that the proposed technique provides high security with less overhead and delay. 相似文献
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在Ad Hoc网络中,动态拓扑及自由移动的特点使恶意节点发起各种攻击造成网络资源不可用。为此提出移动频率(MF,Mobile Frequency)评估节点移动情况。同时,在AODV的基础上,提出一个基于节点信任度和能量的路由方案,该方案中节点信任度受移动频率影响,下一跳节点的选择由信任度和能量共同决定,并通过区分可信与不可信节点,孤立恶意节点来保证路径上的节点都有足够能量并且安全可信。 相似文献