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1.
关于WSNs中QoS的研究以前都是孤立的,或是特定在某些功能层上的研究,或是特别指定某些应用场景的研究。而论文根据WSNs的参考体系结构,分层讨论了QoS需求的定义以及低层QoS需求对高层QoS需求的影响,从而得出一个整体的QoS框架,然后根据各个QoS需求之间的关系,分析它们之间是否有权衡点以及怎样找到这种权衡关系,以便深入理解WSNs中各QoS需求的互相作用。当无线传感器网络中存在需要考虑QoS支持的业务时,应用设计者能够参照制定详细的QoS需求,系统工程师可以参考评估各个QoS需求之间的权衡关系,从而进行网络的整体设计。  相似文献   

2.
Radio frequency identification and wireless sensor networks are two important wireless technologies that have a wide variety of applications in current and future systems. RFID facilitates detection and identification of objects that are not easily detectable or distinguishable by using conventional sensor technologies. However, it does not provide information about the condition of the objects it detects. WSN, on the other hand, not only provides information about the condition of the objects and environment but also enables multihop wireless communications. Hence, the integration of these technologies expands their overall functionality and capacity. This article investigates recent research work and applications that integrate RFID with sensor networks. Four classes of integration are discussed: integrating tags with sensors, integrating tags with WSN nodes and wireless devices, integrating readers with WSN nodes and wireless devices, and a mix of RFID and WSNs. Finally, a discussion of new challenges and future work is presented.  相似文献   

3.
Debugging in distributed environments, such as wireless sensor networks (WSNs), which consist of sensor nodes with limited resources, is an iterative and occasionally laborious process for programmers. In sensor networks, it is not easy to find unintended bugs that arise during development and deployment, and that are due to a lack of visibility into the nodes and a dearth of effective debugging tools. Most sensor network debugging tools are not provided with effective facilities such as real‐time tracing, remote debugging, or a GUI environment. In this paper, we present a hybrid debugging framework (HDF) that works on WSNs. This framework supports query‐based monitoring and real‐time tracing on sensor nodes. The monitoring supports commands to manage/control the deployed nodes, and provides new debug commands. To do so, we devised a debugging device called a Docking Debug‐Box (D2‐Box), and two program agents. In addition, we provide a scalable node monitor to enable all deployed nodes for viewing. To transmit and collect their data or information reliably, all nodes are connected using a scalable node monitor applied through the Internet. Therefore, the suggested framework in theory does not increase the network traffic for debugging on WSNs, and the traffic complexity is nearly O(1).  相似文献   

4.
In recent years, Wireless Sensor Networks (WSNs) have demonstrated successful applications for both civil and military tasks. However, sensor networks are susceptible to multiple types of attacks because they are randomly deployed in open and unprotected environments. It is necessary to utilize effective mechanisms to protect sensor networks against multiple types of attacks on routing protocols. In this paper, we propose a lightweight intrusion detection framework integrated for clustered sensor networks. Furthermore, we provide algorithms to minimize the triggered intrusion modules in clustered WSNs by using an over‐hearing mechanism to reduce the sending alert packets. Our scheme can prevent most routing attacks on sensor networks. In in‐depth simulation, the proposed scheme shows less energy consumption in intrusion detection than other schemes. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

5.
Wireless sensor networks (WSNs) have been widely investigated in the past decades because of its applicability in various extreme environments. As sensors use battery, most works on WSNs focus on energy efficiency issues (e.g., local energy balancing problems) in statically deployed WSNs. Few works have paid attention to the global energy balancing problem for the scenario that mobile sensor nodes can move freely. In this paper, we propose a new routing protocol called global energy balancing routing protocol (GEBRP) based on an active network framework and node relocation in mobile sensor networks. This protocol achieves global energy efficiency by repairing coverage holes and replacing invalid nodes dynamically. Simulation and experiment results demonstrate that the proposed GEBRP achieves superior performance over the existing scheme. In addition, we analyze the delay performance of GEBRP and study how the delay performance is affected by various system parameters.Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

6.
In the past five years, many energy-efficient medium access protocols for all kinds of wireless networks (WSNs) have been proposed. Some recently developed protocols focus on sensor networks with low traffic requirements are based on so-called preamble sampling or low-power listening. The WiseMAC protocol is one of the first of this kind and still is one of the most energy-efficient MAC protocols for WSNs with low or varying traffic requirements. However, the high energy-efficiency of WiseMAC has shown to come at the cost of a very limited maximum throughput. In this paper, we evaluate the properties and characteristics of a WiseMAC implementation in simulation and on real sensor hardware. We investigate on the energy-consumption of the prototype using state-of-the-art evaluation methodologies. We further propose and examine an enhancement of the protocol designed to improve the traffic-adaptivity of WiseMAC. By conducting both simulation and real-world experiments, we show that the WiseMAC extension achieves a higher maximum throughput at a slightly increased energy cost both in simulation and real-world experiments.  相似文献   

7.
Transmission and distribution systems for electricity have undergone a technological revolution in terms of operation and management using computer networks, automation, remote sensing, and information and communication technologies to improve the performance of digital electronic meters. This work describes the integration of a wireless sensor networks (WSNs)–based communication system with an electrical energy‐measurement structure, to verify the feasibility of large‐scale installation of intelligent electronic meters in low‐voltage consumer units. The study is based on simulations, using Castalia, considering 2 scenarios, the first in a flat network and the second in a hierarchical network of WSNs to analyze the feasibility of sending messages from intelligent electronic meters to the concessionaires through a ZigBee network.In addition, the time requirements of the IEC 61850 standard for sending and receiving manufacturing message specifications and generic object‐oriented substation event type messages are verified. This work demonstrated the technical feasibility of using WSNs for different node densities by region and evaluated the location of the sink node, and adequate infrastructures for WSNs were found. This extends time checks for both vertical (usually for supervision) and horizontal (used for protection) messages. The proposed model has great potential to use a WSN infrastructure and to evaluate if this infrastructure allows data transmission of the protocols used in smart grids, mainly verifying the requirements of transmission times required by each application.  相似文献   

8.
基于P2P的无线传感器网络应用架构研究   总被引:3,自引:0,他引:3  
通过基础网络互联多个传感器网络,为用户提供大规模、大范围、多样化的信息服务成为未来无线传感器网络的应用模式之一。据此,提出了一种基于P2P(Peer-to—Peer)技术的无线传感器网络应用架构。采用P2P技术,解决了大数据量的通信瓶颈,传感器网络亦可自由加入、变更或退出,方便部署,网络可扩展性好.同时屏蔽底层网络差异及多种接入方式.为用户提供多个访问入口。  相似文献   

9.
Key management has remained a challenging issue in wireless sensor networks (WSNs) due to the constraints of sensor node resources. Various key management schemes that trade off security and operational requirements have been proposed in recent years. In this article, we first examine the security and operational requirements of WSNs and then review five key management protocols: Eschenauer, Du, LEAP, SHELL, and Panja. Eschenauer's scheme is a classical random key distribution scheme for WSNs. Du's scheme improves on Eschenauer's scheme by using key matrices. LEAP provides a highly flexible key management scheme using four types of keys. SHELL focuses on achieving high robustness, and Panja is optimized for hierarchical WSNs. LEAP, SHELL, and Panja support cluster-based operations and are more aligned with current trends as shown by the new standards, IEEE 802.15.4b and the ZigBee "enhanced" standard. Future developments likely will incorporate the features of LEAP and adjustable robustness enhancements from Eschenauer or Du; extremely security-critical applications may benefit from restructuring SHELL to ease implementation and maintenance. Developments for extremely large WSNs should consider improving Panja's scheme due to its hierarchical scalability feature.  相似文献   

10.
Wireless sensor networks (WSNs) are composed of thousands of smart‐sensing nodes, which capture environment data for a sink node. Such networks present new challenges when compared with traditional computer networks, namely in terms of smart node hardware constraints and very limited energy resources. Ubiquitous computing can benefit from WSNs from the perspective that sensed data can be used instead of the user without explicit intervention, turning ubiquitous computing into a reality. Internet connectivity in WSNs is highly desirable, featuring sensing services at a global scale. Two main approaches are considered: proxy based or sensor node stack based. This second approach turns sensors into data‐producing hosts also known as ‘The Internet of Things’. For years, the TCP/IP (Transmission Control Protocol/Internet Protocol) suite was considered inappropriate for WSNs, mainly due to the inherent complexity and protocol overhead for such limited hardware. However, recent studies made connecting WSNs to the Internet possible, namely using sensor node stack based approaches, enabling integration into the future Internet. This paper surveys the current state‐of‐the‐art on the connection of WSNs to the Internet, presents related achievements, and provides insights on how to develop IP‐based communication solutions for WSNs today. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

11.
Directed diffusion (DD) is a promising data‐centric routing scheme for wireless sensor networks (WSNs). But the heavy flooding overhead involved in interest propagation causes scalability issues when DD is applied in large scale, interactive and dynamically changing sensor networks. To solve this problem, we propose a scalable version of DD called gossip‐based scalable directed diffusion (GSDD) in this paper. GSDD uses the same routing framework as DD but integrates gossiping in interest propagation and employs dynamic regional gossiping in path exploration phase to reduce the flooding overhead. Our analysis and simulation results demonstrate that GSDD is able to reduce the data delivery cost of DD by up to 25%; thus, significantly reduce energy consumption and prolong the lifetime of sensor nodes. Therefore, GSDD overcomes the scalability problem of DD and is suitable for large‐scale WSNs. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

12.
Most of the existing intrusion detection frameworks proposed for wireless sensor networks (WSNs) are computation and energy intensive, which adversely affect the overall lifetime of the WSNs. In addition, some of these frameworks generate a significant volume of IDS traffic, which can cause congestion in bandwidth constrained WSNs. In this paper, we aim to address these issues by proposing a game theory based multi layered intrusion detection framework for WSNs. The proposed framework uses a combination of specification rules and a lightweight neural network based anomaly detection module to identify the malicious sensor nodes. Additionally, the framework models the interaction between the IDS and the sensor node being monitored as a two player non-cooperative Bayesian game. This allows the IDS to adopt probabilistic monitoring strategies based on the Bayesian Nash Equilibrium of the game and thereby, reduce the volume of IDS traffic introduced into the sensor network. The framework also proposes two different reputation update and expulsion mechanisms to enforce cooperation and discourage malicious behavior among monitoring nodes. These mechanisms are based on two different methodologies namely, Shapley Value and Vickery–Clark–Grooves (VCG) mechanism. The complexity analysis of the proposed reputation update and expulsion mechanisms have been carried out and are shown to be linear in terms of the input sizes of the mechanisms. Simulation results show that the proposed framework achieves higher accuracy and detection rate across wide range of attacks, while at the same time minimizes the overall energy consumption and volume of IDS traffic in the WSN.  相似文献   

13.
In wireless sensor networks (WSNs), resource-constrained nodes are expected to operate in highly dynamic and often unattended environments. Hence, support for intelligent, autonomous, adaptive and distributed resource management is an essential ingredient of a middleware solution for developing scalable and dynamic WSN applications. In this article, we present a resource management framework based on a two-tier reinforcement learning scheme to enable autonomous self-learning and adaptive applications with inherent support for efficient resource management. Our design goal is to build a system with a bottom-up approach where each sensor node is responsible for its resource allocation and task selection. The first learning tier (micro-learning) allows individual sensor nodes to self-schedule their tasks by using only local information, thus enabling a timely adaptation. The second learning tier (macro-learning) governs the micro-learners by tuning their operating parameters so as to guide the system towards a global application-specific optimization goal (e.g., maximizing the network lifetime). The effectiveness of our framework is exemplified by means of a target tracking application built on top of it. Finally, the performance of our scheme is compared against other existing approaches by simulation. We show that our two-tier reinforcement learning scheme is significantly more efficient than traditional approaches to resource management while fulfilling the application requirements.  相似文献   

14.
We derive a new investigation for the wireless sensor networks (WSNs) when the underlying sensor node distribution strategies have strong influence on event specific communication performance. In this paper, we inclusively evaluated eight sensor network distributions namely: normal, gamma, exponential, beta, generalized inverse Gaussian, poison, Cauchy and Weibull. We designed and illustrated our proposed model with these node distributions for data dissemination. Moreover, performance evaluation matrices like sense count, receive count and receive redundant count are also evaluated. Additionally, we emphasized over the routing protocol behavior for different distribution strategies in the deployed WSN framework. Finally, simulation analysis has been carried out to prove the validity of our proposal. However, routing protocol for WSNs seems intractable to the sensor node distribution strategies when varied from one to another in the scenario.  相似文献   

15.
Location awareness remains the key for many potential future applications of distributed wireless ad hoc sensor networks (WSNs). While the location of a WSN node can be estimated by incorporating Global Positioning System (GPS) devices, it is not suitable to embed GPS receivers in every node considering the cost and size of these devices as well as from an optimization point of view. However, a small number of WSNs nodes called anchor nodes are able to resolve their location either through fixed deployment or using GPS receivers, and thereby provide the reference framework for localization of other nodes. The measurement devices in individual nodes are often erroneous for tiny WSNs nodes, and hence, robustness is a major issue for localization. In this paper, a theoretical localization framework in the presence of noise is postulated, which achieves accurate positioning compared to the existing theoretical approaches. The paired measurement localization (PML) strategy is evaluated through simulations under various noise conditions and environmental modeling, and practically verified by a testbed implementation with real motes. The results corroborate the improved positioning as well as the robustness of PML for ad hoc wireless sensor networks in the presence of noise.  相似文献   

16.
Wireless sensor networks (WSNs) are appealing in obtaining fine-granular observations about the physical world. Due to the fact that WSNs are composed of a large number of low-cost and energy-constrained sensor nodes, along with the notorious time-varying and error-prone nature of wireless links, scalable, robust and energy-efficient data dissemination techniques are needed for the emerging WSN applications such as environment monitoring and surveillance. In this paper, we examine this emerging field from the point of view of supply chain management and propose a hybrid data dissemination framework for WSNs. In particular, for each sensing task, the whole sensor field is conceptually partitioned into several functional regions based on the supply chain management methodology. Different routing schemes are applied to different regions in order to provide better performance in terms of reliability and energy consumption. For this purpose, we also propose a novel zone flooding scheme, essentially a combination of conventional geometric routing and flooding techniques. Our hybrid data dissemination framework features low overhead, high reliability, good scalability and flexibility, and preferable energy efficiency. Detailed simulation studies are carried out to validate the effectiveness and efficiency of our scheme.  相似文献   

17.
Wireless sensor networks are an important research area that has attracted considerable attention. Most of this attention, however, has been concentrated on WSNs that collect scalar data such as temperature and vibration. Scalar data can be insufficient for many applications such as automated surveillance and traffic monitoring. In contrast, camera sensors collect visual data, which are rich in information and hence offer tremendous potential when used in WSNs. However, they raise new challenges such as the transmission of visual data with high computational and bandwidth requirements in mainly low-power visual sensor networks. In this article we highlight the challenges and opportunities of VSNs. We discuss major research issues of VSNs, specifically camera coverage optimization, network architecture, and low-power visual data processing and communication, and identify enabling approaches in this area.  相似文献   

18.
As considerable progress has been made in wireless sensor networks (WSNs), we can expect that sensor nodes will be applied in industrial applications. Most available techniques for WSNs can be transplanted to industrial wireless sensor networks (IWSNs). However, there are new requirements of quality of service (QoS), that is, real‐time routing, energy efficiency, and transmission reliability, which are three main performance indices of routing design for IWSNs. As one‐hop neighborhood information is often inadequate to data routing in IWSNs, it is difficult to use the conventional routing methods. In the paper, we propose the routing strategy by taking the real‐time routing performance, transmission reliability, and energy efficiency (TREE, triple R and double E) into considerations. For that, each sensor node should improve the capability of search range in the phase of data route discovery. Because of the increase of available information in the enlarged search range, sensor node can select more suitable relay node per hop. The real‐time data routes with lower energy cost and better transmission reliability will be used in our proposed routing guideline. By comparing with other routing methods through extensive experimental results, our distributed routing proposal can guarantee the diversified QoS requirements in industrial applications. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

19.
A survey of transport protocols for wireless sensor networks   总被引:4,自引:0,他引:4  
In this article we present a survey of transport protocols for wireless sensor networks (WSNs). We first highlight several unique aspects of WSNs, and describe the basic design criteria and challenges of transport protocols, including energy-efficiency, quality of service, reliability, and congestion control. We then provide a summary and comparison of existing transport protocols for WSNs. Finally, we discuss several open research problems.  相似文献   

20.
Packet size optimization is a critical issue in wireless sensor networks (WSNs) for improving many performance metrics (eg, network lifetime, delay, throughput, and reliability). In WSNs, longer packets may experience higher loss rates due to harsh channel conditions. On the other hand, shorter packets may suffer from greater overhead. Hence, the optimal packet size must be chosen to enhance various performance metrics of WSNs. To this end, many approaches have been proposed to determine the optimum packet size in WSNs. In the literature, packet size optimization studies focus on a specific application or deployment environment. However, there is no comprehensive and recent survey paper that categorizes these different approaches. To address this need, in this paper, recent studies and techniques on data packet size optimization for terrestrial WSNs, underwater WSNs, wireless underground sensor networks, and body area sensor networks are reviewed to motivate the research community to further investigate this promising research area. The main objective of this paper is to provide a better understanding of different packet size optimization approaches used in different types of sensor networks and applications as well as introduce open research issues and challenges in this area.  相似文献   

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