Detection of Insider Selective Forwarding Attack Based on Monitor Node and Trust Mechanism in WSN

The security problems of wireless sensor networks (WSN) have attracted people’s wide attention. In this paper, after we have summarized the existing security problems and solutions in WSN, we find that the insider attack to WSN is hard to solve. Insider attack is different from outsider attack, because it can’t be solved by the traditional encryption and message authentication. Therefore, a reliable secure routing protocol should be proposed in order to defense the insider attack. In this paper, we focus on insider selective forwarding attack. The existing detection mechanisms, such as watchdog, multipath retreat, neighbor-based monitoring and so on, have both advantages and disadvantages. According to their characteristics, we proposed a secure routing protocol based on monitor node and trust mechanism. The reputation value is made up with packet forwarding rate and node’s residual energy. So this detection and routing mechanism is universal because it can take account of both the safety and lifetime of network. Finally, we use OPNET simulation to verify the performance of our algorithm.

The Next-Hop Node Selection Based GPSR in Vehicular Ad Hoc Networks

Vehicular Ad hoc Networks (VANETs) which is a special form of Mobile Ad hoc Networks (MANETs) has promising application prospects in the future. Due to the rapid changing of topology structure, how to find a route which can guarantee Quality of Service (QoS) is an important issue in VANETs. This paper presents an improved Greedy Perimeter Stateless Routing (GPSR) protocol based on our proposed next-hop node selection mechanism. Firstly, we define the link reliability in two cases which take the movement direction angle between two vehicles into consideration. Then we propose a next-hop node selection mechanism based on a weighted function which consists of link reliability between the sender node and next-hop candidate node, distance between next-hop candidate node and the destination, movement direction angle of next-hop candidate node. At last, an improved GPSR protocol is proposed based on the next-hop node selection mechanism. Simulation results are presented to evaluate the performance of the improved GPSR protocol, which shows that the performance including packet delivery ratio and average end-to-end delay of the proposed protocol is better in some situations.

基于模糊评判的无线传感器网络簇间数据转发算法

由于无线传感器网络在簇间数据转发过程中消耗能量较大、转发效率低,导致数据在转发过程中容易失效。为此,提出基于模糊评判的无线传感器网络簇间数据转发算法。建立无线传感器网络模型和通信模型,明确节点的运行方式和转发数据所消耗的能量,构建模糊综合评判模型,选取梯形隶属度函数计算传感器节点的相似度和活跃度,找出最佳转发节点,完成数据转发任务。仿真结果表明,所提算法的第一个节点死亡轮数和网络失效轮数最高为167和178,在仿真轮数达到1000轮时,该算法剩余的网络能量和节点平均能量分别为4 J和0.01 J,证明所提算法在数据转发过程中可消耗最少的能量,高效率地完成数据转发任务。

基于DTN路由的多通路精准灌溉系统布局设计

为进一步提升我国智能灌溉装备的综合作业效率,从多通路实施与精准化控制角度展开布局设计。以灌溉系统的作业原理及田间信息获取特征为出发点,建立灌溉网络的DTN路由算法模型,实施网络节点的规划分配与通道布置,形成精准性的逻辑控制流程及节点网络相互执行关系。进行系统性的灌溉试验,结果表明:基于DTN路由算法的多通路精准灌溉系统布局正确可行,信息投递成功率可达94.13%,节点转发率可达96.07%,各信息传递的实时准确,各阀门组件的动作协调,综合灌溉效率实现了高于90%的优化目标,是DTN路由控制理念在灌溉装备领域的应用创新思路之一,具有较好的推广意义。

结合节点特征和非合作博弈的选择性转发攻击检测

针对无线传感器网络的选择性转发攻击行为,提出了一种结合节点特征和非合作博弈的选择性转发攻击检测(node characteristics and non-cooperative game for selective forwarding attack detection,NC-NCG)方法。该方法通过设置独立监督网络环境,将节点特征中的转发率与门限阈值进行比较,计算小于阈值节点的当前转发率与T时间内平均转发率的偏离程度,根据偏离程度进行二次判定,以提高选择性转发攻击的检测率。同时为提高网络吞吐量,构建了不完全信息的非合作博弈模型,迫使可疑节点参与网络功能,实现节点快速识别。仿真实验结果表明,该方法不仅能够有效识别选择性转发攻击,而且在资源有限的情况下,可以提高网络吞吐量并延长网络生命周期。

一种基于空洞节点检测的可靠无人机自组网路由协议

针对高动态无人机自组网中节点之间链路生存时间(Link Live Time,LLT)短和节点遭遇路由空洞次数多的问题,提出了一种基于空洞节点检测的可靠无人机自组网路由协议——GPSR-HND(Greedy Perimeter Stateless Routing Based on Hollow Node Detection)。GPSR-HND协议中,转发节点通过空洞节点检测机制检测邻居节点状态,将有效邻居节点加入待选邻居节点集;然后基于层次分析法(Analytic Hierarchy Process,AHP)的多度量下一跳节点选择机制从待选邻居节点集中选择权重最大的邻居节点贪婪转发数据;如果待选邻居节点集为空,则从空洞邻居节点集中选择权重最大的空洞节点启动改进的周边转发机制,寻找可恢复贪婪转发模式的节点。与GPSR-NS协议和GPSR协议相比,GPSR-HND协议表现出了更好的性能,包括平均端到端时延和丢包率的改善,以及吞吐量的提高。

全渠道供应链网络节点约束存储转发调度方法

在全渠道供应链网络中,资源请求被阻塞,出现资源调度拥挤现象,导致调度时间变长,影响整体调度效率。因此,提出了全渠道供应链网络节点约束存储转发调度方法。根据搭建网络节点约束存储转发调度框架,计算资源请求阻塞概率,利用时移多层图法实现空间和时间资源请求指令的双向传送,避免出现请求阻塞问题。构建调度决策目标函数,调整网络节点约束存储转发顺序,确定供应链网络节点约束下存储转发成功率,实现节点约束存储转发调度。实验结果可知,该方法调度时长最短为30 s,且调度路径与预先设定路径吻合,具有高效调度效果。

能耗均衡与节能的自适应水下路由协议

针对水下传感器网络中节点能耗不均衡和能量有限的问题,提出一种能耗均衡与节能的自适应水下路由协议ECBES(energy consumption balanced and energy saving adaptive underwater routing protocol)。构建双区非均匀分层拓扑。基于能耗均衡因子,利用拓扑和节点剩余能量计算节点转发优先级,实现自适应转发节点选择,均衡网络能耗。与此同时,通过候选转发区域各分区域中节点参与转发数据包的比例确定次优候选转发区域,将次优候选转发区域作为初始策略,利用策略迭代思想确定最优候选转发区域,保证投递率的同时减少不同网络规模中重复数据包的转发,降低网络的整体能耗。仿真结果表明,ECBES相比VBF、ES-VBF和ALRP,在不同节点数量下,节点死亡率均最低,在保证数据包投递率的同时,能耗最少。

基于链路预测和能量感知的机会路由协议研究

在无线传感器(Wireless Sensors Networks,WSN)中,由于节点能量有限,可能导致节点过早死亡,引起网络结构发生变化,链路稳定性变差。针对该问题文中提出了一种基于链路预测和能量感知的机会路由协议ELPOR(Opportunistic Routing Protocol Based on Link Prediction and Energy Sensing,ELPOR).该协议综合考虑节点能量和各节点之间链路连接的概率,从潜在的候选转发集中选择一个中继节点,以实现能量的高效利用和数据的可靠传输。仿真结果表明,该协议能够有效均衡网络能耗、提高吞吐量和延长网络生存周期。

利用节点度的无线区块链转发机制

针对目前区块链系统中传播区块消耗大,难以适配无线环境下动态变化网络拓扑的问题,设计了一种基于节点度的无线区块链转发机制,通过复杂网络传播模型确定最低转发下限,在综合考虑能量消耗、吞吐量和安全性的条件下确定最优的转发比例。节点根据自身度指标与转发比例确定转发消息的邻居数量,通过节点邻居的度信息,分布式调整向邻居发送消息的概率,提高了网络中消息的递送效率。仿真结果表明,所提机制性能与洪泛机制相近,但消耗大大减小,各项性能均优于传统的Gossip机制。

RPL路由协议的改进方法及性能分析

针对能量损耗问题,为增加节点在网络中的有效存活时间和延长网络的使用寿命,文章提出了一种平衡关键传感器节点能量损耗的解决方案E NPS-RPL。该方案依据关键节点的转发数据包次数调节有向无环图的构建,并预估关键节点的平均能量消耗,从而改变路径的选取,以延长无线传感网络的有效生存时间。通过比较ELT、ETX、RPL与E_(NPS)-RPL方案在链路质量和网络信息传递中的性能参数,结果表明,E_(NPS)-RPL方案在整个网络范围内转发报文的平均能量消耗最低,为44个单位;当网络节点数为70时,E_(NPS)-RPL方案具有较佳的220跳的网络存活时间。E_(NPS)-RPL方案有效改善了传感器节点在无线传感网中的能量损耗,从而延长了使用寿命。

On-demand multicast routing protocol based on node classification in MANET

An improved on-demand multicast routing protocol(ODMRP), node classification on-demand multicast routing protocol(NC-ODMRP), which is based on node classification in mobile ad hoc networks was proposed. NC-ODMRP classifies nodes into such three categories as ordinary node, forwarding group(FG) node, neighbor node of FG node according to their history forwarding information. The categories are distinguished with different weights by a weight table in the nodes. NC-ODMRP chooses the node with the highest weight as an FG node during the setup of forwarding group, which reduces a lot of redundant FG nodes by sharing more FG nodes between different sender and receiver pairs. The simulation results show that NC-ODMRP can reduce more than 20% FG number of ODMRP, thus enhances nearly 14% data forwarding efficiency and 12% energy consumption efficiency when the number of multicast senders is more than 5.

Physical Layer Deterministic Network Coding Using PUM Turbo Codes over AWGN Channel, N Nodes through a Base Station Scenario

Network Coding (NC) is a recent technique which is used to improve the transmission data rate and the power efficiency. These goals are obtained by combining data together before transmitting them, resulting to less transmitted data that carry the same amount of information. NC research work over the physical layer and the upper layers are popular and needed to be more investigated. In this paper, we propose a practical system of large-number of connected multi-source network coding (LMSNC), at the physical layer that exploits the broadcast nature of the wireless channel, using the practical and bandwidth-efficient schemes decode-and-forward (DF) and then compare it with Amplify and Forward (AF). The theoretical analysis and the simulation results show the effect of the noise when it cumulates in AF system and how DF is solving this severe default. Moreover, we consider the MSNC for Small-number of connected sources (SMSNC) and the two-way communication setup where two users exchange their information over an intermediate network node (ideally called Base Station), as two reference cases to compare with. With SMSNC, the number of necessary downlink transmissions from the intermediate node to the users is reduced, and thus the throughput is increased. Simulation results obtained using high-performance non-binary turbo codes, based on Partial Unit Memory (PUM) codes (4, 2, 1, 4) and (8, 4, 3, 8);confirm that combining PUM Turbo Code (PUMTC) and NC in the proposed MSNC setup gives almost the same BER performance as that for SMSNC at the small number of processing steps mainly when PUMTC (8, 4, 3, 8) is performed, which is required to retrieve the received coded messages. In the scenario of AF, combining packets results to cumulate the noise, which justifies the reason we decided to increase the number of transmitted coded messages in the network, i.e., the BER performance improves when sending extra coded messages. Finally, the possibility for a trade-off among BER, data rate and the number of transmitted coded messages is shown for LMSNC through graphics and simulation results.

Ad Hoc On-Demand Multipath Distance Vector Routing Protocol Based on Node State

To improve the performance of Ad hoc on-demand multipath distance vector (AOMDV) protocol, we proposed NS-AOMDV which is short for “AOMDV based on node state”. In NS-AOMDV, we introduce node state to improve AOMDV’s performance in selecting main path. In route discovery process, the routing update rule calculates the node weight of each path and sorts the path weight by descending value in route list, and we choose the path which has the largest path weight for data transmission. NS-AOMDV also uses the technology of route request (RREQ) packet delay forwarding and energy threshold to ease network congestion, limit the RREQ broadcast storm, and avoid low energy nodes to participate in the establishment of the path. The results of simulation show that NS-AOMDV can effectively improve the networks’packets delivery rate, throughput and normalized routing overhead in the situation of dynamic network topology and heavy load.

An Efficient Billing Scheme for Trusted Nodes Using Fuzzy Logic in Wireless Sensor Networks

Extending the lifetime of the wireless sensor networks (WSNs), where recharging sensors is not always possible, has been a major concern for researchers for the past decade. In this paper, we study the cooperation between nodes in wireless sensor networks in forwarding packets to others, and we propose a new collaboration technique which stimulates intermediate nodes to forward packets toward their destination. Some nodes show selfish behavior by denying the forwarding packets to other nodes in commercial networks in an effort to preserve their own energy. This paper applies a technique which is used to prolong the network lifetime, based on a node’s energy and trust value, and additionally incorporates fuzzy logic, which stimulates nodes to forward packets by rewarding cooperation. According to simulation results, the proposed approach surpasses the Nuglets (virtual currency) approach and the Reputation approach in network energy and thus prolongs the network lifetime. Additionally, our proposed approach demonstrates better results in the number of dropped packets, PDR and forwarded packets to neighboring nodes.

基于中继节点的多跳CR Ad Hoc网络广播算法

针对避免广播冲突的CR Ad Hoc网络的分布式广播协议广播成功率低和基于选择性广播信道集的低延迟广播算法广播冲突率高的问题,提出基于中继节点选择的多跳CR Ad Hoc网络广播算法。根据节点可用信道集的大小和基于邻居度的转发概率选取中继节点,并对相应中继节点的可用信道集随机左移,在保证一定广播成功率、广播时延和广播冲突率的前提下,降低节点转发率,减少网络中的冗余信息;建立综合评价函数对广播算法的综合性能进行了定量分析;给出广播冲突概率推导。仿真结果表明,该算法与分布式广播协议相比,提高了广播成功率,降低了广播时延;与低延迟广播算法相比,降低了节点转发率和广播冲突概率。根据综合评价函数,该广播算法的综合性能更好。

基于无线传感器网络的信息传播研究

为了研究无线传感器网络中的信息传播问题,结合CSMA/CA协议和传染病模型的研究办法,建立了一种离散的信息传播模型。该模型描述了感染节点在竞争信道成功后以广播的形式将信息传播给其邻居节点。仿真研究表明,转发概率、节点的通信半径和节点密度等因素对传感器网络中的信息传播速度有较大的影响,动态地调节这些参数可以将信息尽快地传遍整个网络。

隐式IPv6路由高速转发路由探测算法

因受网络通信信道干扰以及多径特征的影响,隐式IPv6网络在数据转发过程中链路均衡性差,提出隐式IPv6路由高速转发路由探测算法。构建隐式IPv6路由转发的节点定位部署模型,采用波特间隔均衡控制方法进行隐式IPv6路由转发链路信道均衡设计,提取路由高速数据转发的统计特征量;根据关联规则融合调度方法控制其能耗,在全网能量均衡约束模型下实现链路转发协议优化,根据数据转发负载均衡调度模型实现隐式IPv6路由高速转发路由探测。仿真结果表明,采用该方法进行隐式IPv6路由转发速率高、数据转发均衡性好、输出误码率低、链路均衡性好。

无线传感网络中基于转发节点优化的地理位置路由

由于复杂度低、扩展性好,地理位置路由广泛应用于无线传感网络(WSN)。传统地理位置路由只依据节点位置决策下一跳转发节点,并没有考虑节点能耗。为此,提出转发节点优化的地理位置路由(FNO-GR),旨在提升网络寿命,减少死亡节点数。FNO-GR路由构建邻居节点集,依据离信宿距离,从邻居节点集中选择候选转发节点,并考虑节点剩余能量,从候选转发节点中选择最优的节点作为下一跳转发节点。仿真结果表明,与最短地理位置路由(SGR)协议相比,FNO-GR路由的平均网络寿命提升约5.08%,死亡节点数下降了约7.99。

改进分层前推回代法的煤矿供电系统潮流研究

煤矿中大量大功率电气设备的投入运行,导致煤矿拓扑结构复杂、线路过负荷、电能损耗严重。针对此问题,本文以煤矿供电系统为研究对象,改进传统分层前推回代潮流算法,节点分层配电网逻辑拓扑图,明确煤矿配电网拓扑结构,并分别从末梢节点和源点开始进行前推回代计算,根据得到的功率损耗与电流电压数据分析煤矿供电系统电能损耗与功率因数,计算无功补偿容量,得到功率损耗与电流电压数据,并分析煤矿供电系统电能损耗与功率因数,判断是否需要无功补偿并计算无功补偿容量,这有利于提高供电系统稳定性,减少煤矿企业电能损耗。