针对命名数据网络(named data networking,NDN)中缓存冗余高、资源利用率低的问题,提出基于数据冗余包的协同缓存放置策略(cooperative cache placement strategy based on da-ta redundancy packet,CCPS-DRP)。该策略先对网络进行社区...针对命名数据网络(named data networking,NDN)中缓存冗余高、资源利用率低的问题,提出基于数据冗余包的协同缓存放置策略(cooperative cache placement strategy based on da-ta redundancy packet,CCPS-DRP)。该策略先对网络进行社区划分,再利用复杂网络中节点介数确定关键路由节点,将数据冗余包中的相同数据副本存放于其中,并动态管理冗余数据副本,实现关键节点集中管理与动态冗余清理的协同机制,以减少相同数据内容的重复缓存,使路由节点中的缓存容量得到充分利用,降低网络负载。实验结果表明,无论在均匀分布或高度偏斜分布的场景下,还是在严格资源限制或有较高资源的场景下,CCPS-DRP在缓存命中率和平均请求时延方面的性能均明显优于常见的随处缓存策略、概率缓存策略等,其通过协同缓存与冗余控制显著提升了网络性能。展开更多
This paper presents the hypermedia data model based on the infinity RS image information system we have developed.The hypermedia data model consists of different semantic units called nodes,and the associations betwee...This paper presents the hypermedia data model based on the infinity RS image information system we have developed.The hypermedia data model consists of different semantic units called nodes,and the associations between nodes are called links.This paper proposes three kinds of nodes (interior node,physical node and complex node) and two kinds of links (plane network structure link,hyper_cube network structure links).The hypermedia information system,based on the model and the basic data layer (the infiniy RS image),represents a digital globe.An approach to the “Getting Lost in the Hyper_space” problem is presented.The approach using the hypermedia data model is an efficient way of handling a large number of RS images in various geographical information systems.展开更多
Recently, the exponential rise in communication system demands has motivated global academia-industry to develop efficient communication technologies to fulfill energy efficiency and Quality of Service (QoS) demands. ...Recently, the exponential rise in communication system demands has motivated global academia-industry to develop efficient communication technologies to fulfill energy efficiency and Quality of Service (QoS) demands. Wireless Sensor Network (WSN) being one of the most efficient technologies possesses immense potential to serve major communication purposes including civil, defense and industrial purposes etc. The inclusion of sensor-mobility with WSN has broadened application horizon. The effectiveness of WSNs can be characterized by its ability to perform efficient data gathering and transmission to the base station for decision process. Clustering based routing scheme has been one of the dominating techniques for WSN systems;however key issues like, cluster formation, selection of the number of clusters and cluster heads, and data transmission decision from sensors to the mobile sink have always been an open research area. In this paper, a robust and energy efficient single mobile sink based WSN data gathering protocol is proposed. Unlike existing approaches, an enhanced centralized clustering model is developed on the basis of expectation-maximization (EEM) concept. Further, it is strengthened by using an optimal cluster count estimation technique that ensures that the number of clusters in the network region doesn’t introduce unwanted energy exhaustion. Meanwhile, the relative distance between sensor node and cluster head as well as mobile sink is used to make transmission (path) decision. Results exhibit that the proposed EEM based clustering with optimal cluster selection and optimal dynamic transmission decision enables higher throughput, fast data gathering, minima delay and energy consumption, and higher展开更多
Clustering is the most significant task characterized in Wireless Sensor Networks (WSN) by data aggregation through each Cluster Head (CH). This leads to the reduction in the traffic cost. Due to the deployment of the...Clustering is the most significant task characterized in Wireless Sensor Networks (WSN) by data aggregation through each Cluster Head (CH). This leads to the reduction in the traffic cost. Due to the deployment of the WSN in the remote and hostile environments for the transmission of the sensitive information, the sensor nodes are more prone to the false data injection attacks. To overcome these existing issues and enhance the network security, this paper proposes a Secure Area based Clustering approach for data aggregation using Traffic Analysis (SAC-TA) in WSN. Here, the sensor network is clustered into small clusters, such that each cluster has a CH to manage and gather the information from the normal sensor nodes. The CH is selected based on the predefined time slot, cluster center, and highest residual energy. The gathered data are validated based on the traffic analysis and One-time Key Generation procedures to identify the malicious nodes on the route. It helps to provide a secure data gathering process with improved energy efficiency. The performance of the proposed approach is compared with the existing Secure Data Aggregation Technique (SDAT). The proposed SAC-TA yields lower average energy consumption rate, lower end-to-end delay, higher average residual energy, higher data aggregation accuracy and false data detection rate than the existing technique.展开更多
In Wireless Sensor Network (WSNs), sensor nodes collect data and send them to a Base Station (BS) for further processing. One of the most issues in WSNs that researchers have proposed a hundred of technique to solve i...In Wireless Sensor Network (WSNs), sensor nodes collect data and send them to a Base Station (BS) for further processing. One of the most issues in WSNs that researchers have proposed a hundred of technique to solve its impact is the energy constraint since sensor nodes have small battery, small memory and less data processing with low computational capabilities. However, many researches efforts have focused on how to prolong the battery lifetime of sensor nodes by proposing different routing, MAC, localization, data aggregation, topology construction techniques. In this paper, we will focus on routing techniques which aim to prolonging the network lifetime. Hence, we propose an Energy-Efficient Routing technique in WSNs based on Stationary and Mobile nodes (EERSM). Sensing filed is divided into intersected circles which contain Mobile Nodes (MN). The proposed data aggregation technique via the circular topology will eliminate the redundant data to be sent to the Base Station (BS). MN in each circle will rout packets for their source nodes, and move to the intersected area where another MN is waiting (sleep mode) to receive the transmitted packet, and then the packet will be delivered to the next intersected area until the packet is arrived to the BS. Our proposed EERSM technique is simulated using MATLAB and compared with conventional multi-hop techniques under different network models and scenarios. In the simulation, we will show how the proposed EERSM technique overcomes many routing protocols in terms of the number of hops counted when sending packets from a source node to the destination (i.e. BS), the average residual energy, number of sent packets to the BS, and the number of a live sensor nodes verse the simulation rounds.展开更多
图垂直联邦学习是一种结合图数据和垂直联邦学习的分布式机器学习方法,广泛应用于金融服务、医疗健康和社交网络等领域。该方法在保护隐私的同时,利用数据多样性显著提升模型性能。然而,研究表明图垂直联邦学习容易受到对抗攻击的威胁...图垂直联邦学习是一种结合图数据和垂直联邦学习的分布式机器学习方法,广泛应用于金融服务、医疗健康和社交网络等领域。该方法在保护隐私的同时,利用数据多样性显著提升模型性能。然而,研究表明图垂直联邦学习容易受到对抗攻击的威胁。现有的针对图神经网络的对抗攻击方法,如梯度最大化攻击、简化梯度攻击等方法在图垂直联邦框架中实施时仍然面临攻击成功率低、隐蔽性差、在防御情况下无法实施等问题。为应对这些挑战,提出了一种面向图垂直联邦的对抗攻击方法(Node and Feature Adversarial Attack,NFAttack),该方法分别设计了节点攻击策略与特征攻击策略,从不同维度实施高效攻击。首先,节点攻击策略基于度中心性指标评估节点的重要性,通过连接一定数量的虚假节点以形成虚假边,从而干扰高中心性节点。其次,特征攻击策略在节点特征中注入由随机噪声与梯度噪声构成的混合噪声,进而扰乱分类结果。最后,在6个数据集和3种图神经网络模型上进行实验,结果表明NFAttack的平均攻击成功率达到80%,比其他算法提高了约30%。此外,即使在多种联邦学习防御机制下,NFAttack仍展现出较强的攻击效果。展开更多
文摘针对命名数据网络(named data networking,NDN)中缓存冗余高、资源利用率低的问题,提出基于数据冗余包的协同缓存放置策略(cooperative cache placement strategy based on da-ta redundancy packet,CCPS-DRP)。该策略先对网络进行社区划分,再利用复杂网络中节点介数确定关键路由节点,将数据冗余包中的相同数据副本存放于其中,并动态管理冗余数据副本,实现关键节点集中管理与动态冗余清理的协同机制,以减少相同数据内容的重复缓存,使路由节点中的缓存容量得到充分利用,降低网络负载。实验结果表明,无论在均匀分布或高度偏斜分布的场景下,还是在严格资源限制或有较高资源的场景下,CCPS-DRP在缓存命中率和平均请求时延方面的性能均明显优于常见的随处缓存策略、概率缓存策略等,其通过协同缓存与冗余控制显著提升了网络性能。
文摘This paper presents the hypermedia data model based on the infinity RS image information system we have developed.The hypermedia data model consists of different semantic units called nodes,and the associations between nodes are called links.This paper proposes three kinds of nodes (interior node,physical node and complex node) and two kinds of links (plane network structure link,hyper_cube network structure links).The hypermedia information system,based on the model and the basic data layer (the infiniy RS image),represents a digital globe.An approach to the “Getting Lost in the Hyper_space” problem is presented.The approach using the hypermedia data model is an efficient way of handling a large number of RS images in various geographical information systems.
文摘Recently, the exponential rise in communication system demands has motivated global academia-industry to develop efficient communication technologies to fulfill energy efficiency and Quality of Service (QoS) demands. Wireless Sensor Network (WSN) being one of the most efficient technologies possesses immense potential to serve major communication purposes including civil, defense and industrial purposes etc. The inclusion of sensor-mobility with WSN has broadened application horizon. The effectiveness of WSNs can be characterized by its ability to perform efficient data gathering and transmission to the base station for decision process. Clustering based routing scheme has been one of the dominating techniques for WSN systems;however key issues like, cluster formation, selection of the number of clusters and cluster heads, and data transmission decision from sensors to the mobile sink have always been an open research area. In this paper, a robust and energy efficient single mobile sink based WSN data gathering protocol is proposed. Unlike existing approaches, an enhanced centralized clustering model is developed on the basis of expectation-maximization (EEM) concept. Further, it is strengthened by using an optimal cluster count estimation technique that ensures that the number of clusters in the network region doesn’t introduce unwanted energy exhaustion. Meanwhile, the relative distance between sensor node and cluster head as well as mobile sink is used to make transmission (path) decision. Results exhibit that the proposed EEM based clustering with optimal cluster selection and optimal dynamic transmission decision enables higher throughput, fast data gathering, minima delay and energy consumption, and higher
文摘Clustering is the most significant task characterized in Wireless Sensor Networks (WSN) by data aggregation through each Cluster Head (CH). This leads to the reduction in the traffic cost. Due to the deployment of the WSN in the remote and hostile environments for the transmission of the sensitive information, the sensor nodes are more prone to the false data injection attacks. To overcome these existing issues and enhance the network security, this paper proposes a Secure Area based Clustering approach for data aggregation using Traffic Analysis (SAC-TA) in WSN. Here, the sensor network is clustered into small clusters, such that each cluster has a CH to manage and gather the information from the normal sensor nodes. The CH is selected based on the predefined time slot, cluster center, and highest residual energy. The gathered data are validated based on the traffic analysis and One-time Key Generation procedures to identify the malicious nodes on the route. It helps to provide a secure data gathering process with improved energy efficiency. The performance of the proposed approach is compared with the existing Secure Data Aggregation Technique (SDAT). The proposed SAC-TA yields lower average energy consumption rate, lower end-to-end delay, higher average residual energy, higher data aggregation accuracy and false data detection rate than the existing technique.
文摘In Wireless Sensor Network (WSNs), sensor nodes collect data and send them to a Base Station (BS) for further processing. One of the most issues in WSNs that researchers have proposed a hundred of technique to solve its impact is the energy constraint since sensor nodes have small battery, small memory and less data processing with low computational capabilities. However, many researches efforts have focused on how to prolong the battery lifetime of sensor nodes by proposing different routing, MAC, localization, data aggregation, topology construction techniques. In this paper, we will focus on routing techniques which aim to prolonging the network lifetime. Hence, we propose an Energy-Efficient Routing technique in WSNs based on Stationary and Mobile nodes (EERSM). Sensing filed is divided into intersected circles which contain Mobile Nodes (MN). The proposed data aggregation technique via the circular topology will eliminate the redundant data to be sent to the Base Station (BS). MN in each circle will rout packets for their source nodes, and move to the intersected area where another MN is waiting (sleep mode) to receive the transmitted packet, and then the packet will be delivered to the next intersected area until the packet is arrived to the BS. Our proposed EERSM technique is simulated using MATLAB and compared with conventional multi-hop techniques under different network models and scenarios. In the simulation, we will show how the proposed EERSM technique overcomes many routing protocols in terms of the number of hops counted when sending packets from a source node to the destination (i.e. BS), the average residual energy, number of sent packets to the BS, and the number of a live sensor nodes verse the simulation rounds.
文摘图垂直联邦学习是一种结合图数据和垂直联邦学习的分布式机器学习方法,广泛应用于金融服务、医疗健康和社交网络等领域。该方法在保护隐私的同时,利用数据多样性显著提升模型性能。然而,研究表明图垂直联邦学习容易受到对抗攻击的威胁。现有的针对图神经网络的对抗攻击方法,如梯度最大化攻击、简化梯度攻击等方法在图垂直联邦框架中实施时仍然面临攻击成功率低、隐蔽性差、在防御情况下无法实施等问题。为应对这些挑战,提出了一种面向图垂直联邦的对抗攻击方法(Node and Feature Adversarial Attack,NFAttack),该方法分别设计了节点攻击策略与特征攻击策略,从不同维度实施高效攻击。首先,节点攻击策略基于度中心性指标评估节点的重要性,通过连接一定数量的虚假节点以形成虚假边,从而干扰高中心性节点。其次,特征攻击策略在节点特征中注入由随机噪声与梯度噪声构成的混合噪声,进而扰乱分类结果。最后,在6个数据集和3种图神经网络模型上进行实验,结果表明NFAttack的平均攻击成功率达到80%,比其他算法提高了约30%。此外,即使在多种联邦学习防御机制下,NFAttack仍展现出较强的攻击效果。