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Wireless Sensor Network (WSN) is an emerging technology that shows great promise for various futuristic applications both for mass public and military. The sensing technology combined with processing power and wireless communication makes it lucrative for being exploited in abundance in future. The inclusion of wireless communication technology also incurs various types of security threats. The intent of this paper is to investigate the security related issues and challenges in wireless sensor networks. We identify the security threats, review proposed security mechanisms for wireless sensor networks. We also discuss the holistic view of security for ensuring layered and robust security in wireless sensor networks.

Wireless Sensor Network (WSN) is an emerging technology that shows great promise for various futuristic applications both for mass public and military. The sensing technology combined with processing power and wireless communication makes it lucrative for being exploited in abundance in future. The inclusion of wireless communication technology also incurs various types of security threats. The intent of this paper is to investigate the security related issues and challenges in wireless sensor networks. We identify the security threats, review proposed security mechanisms for wireless sensor networks. We also discuss the holistic view of security for ensuring layered and robust security in wireless sensor networks.

The ability to exchange secret information is critical to many commercial, governmental, and military networks. Wireless sensor intrinsic secrecy is essential for communication confidentiality, health privacy, public safety, information superiority, and economic advantage in the modern information society. Wireless Sensor security schemes have typically evolved from those developed for traditional wire line applications, these schemes do not consider physical properties of the wireless channels. To overcome these problems, this research work develops a foundation for design and analysis of wireless sensor networks with secrecy provided by intrinsic properties such as node spatial distribution, wireless propagation medium, and aggregate network interference.

Recent advances in microelectronic technology have made it possible to construct compact and inexpensive wireless sensors. Sensor networks have received significant attention due to their potential applications from civil to military domains. Since sensors in sensor networks are equipped with energy-limited batteries, energy conservation in such networks is of paramount importance in order to prolong the network lifetime. Sensing coverage and sensor connectivity in sensor networks are two fundamental issues, which have been extensively addressed in the literature, and most existing work on sensing coverage has focused on the (connected) full coverage problem that aims to cover the entire monitored region using the minimum number of sensors. However, in some application scenarios, full coverage is either impossible or unnecessary and a partial coverage with a certain degree guarantee is acceptable. In this paper, we study the connected coverage problem with a given coverage guarantee. We first introduce the partial coverage concept and analyze its properties for the first time in order to prolong the network lifetime. Due to NP-hardness of the concerned problem, we then present a heuristic algorithm which takes into account the partial coverage and sensor connectivity simultaneously. We finally conduct extensive experiments by simulations to evaluate the performance of the proposed algorithm.

Recent advances in microelectronic technology have made it possible to construct compact and inexpensive wireless sensors. Sensor networks have received significant attention due to their potential applications from civil to military domains. Since sensors in sensor networks are equipped with energy-limited batteries, energy conservation in such networks is of paramount importance in order to prolong the network lifetime. Sensing coverage and sensor connectivity in sensor networks are two fundamental issues, which have been extensively addressed in the literature, and most existing work on sensing coverage has focused on the (connected) full coverage problem that aims to cover the entire monitored region using the minimum number of sensors. However, in some application scenarios, full coverage is either impossible or unnecessary and a partial coverage with a certain degree guarantee is acceptable. In this paper, we study the connected coverage problem with a given coverage guarantee. We first introduce the partial coverage concept and analyze its properties for the first time in order to prolong the network lifetime. Due to NP-hardness of the concerned problem, we then present a heuristic algorithm which takes into account the partial coverage and sensor connectivity simultaneously. We finally conduct extensive experiments by simulations to evaluate the performance of the proposed algorithm.

Dissertação de Mestrado em Engenharia Informática apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra ; A Wireless Sensor Network (WSN) typically consists of a large number of nodes performing specific tasks such as measuring or monitoring environmental conditions (temperature, luminosity, humidity, etc.). WSNs once deployed are intended to work for a long period of time. Possible scenarios are the ones where human presence is not possible or encouraged such as battlefield, in military application. Due to the large number of nodes in WSNs, the management and the maintenance of the WSN is a challenging task. To ease the management of WSNs, a monitoring tool is of utmost importance to perform some management tasks such as visualize nodes resources usage (node status), send control message to the nodes and also to provide a general knowledge of the network as whole. Beside of monitoring purpose, the monitoring tool can also be used prior to deployment of a new application on the network, for testing purposes, in order to guarantee that all application requirements are satisfied before deploying it. There are some existing monitoring tools that provide data visualization and also perform control of the nodes on the network. However, none of them provides mechanisms to measure performance related metrics such as packet delay or throughput. This dissertation focuses on WSNs monitoring tools which provide the same features of the other existing tools and also provide mechanism to measure performance related metric. A new WSN monitoring tool based on Octopus was developed which is able to measure packets delay and packet lost. The information about these two QoS parameters is available in a live fashion and also information about past metrics history.

Summarization: Sensor networks are often used to perform monitoring tasks, such as animal and vehicle tracking, or the surveillance of enemy forces in military applications. In this paper we introduce the concept of proximity queries, which allow us to report interesting events, observed by nodes in the network that lie within a certain distance from each other. An event is triggered when a user-programmable predicate is satisfied on a sensor node. We study the problem of computing proximity queries in sensor networks and propose several alternative techniques that differ in the number of messages exchanged by the nodes and the quality of the returned answers. Our solutions utilize a distributed routing index, maintained by the nodes in the network, that is dynamically updated as new observations are obtained by the nodes. This distributed index allows us to efficiently process multiple proximity queries involving several different event types within a fraction of the cost that a straightforward evaluation requires. We present an extensive experimental study to show the benefits of our techniques under different scenarios using both synthetic and real data sets. Our results demonstrate that our algorithms scale better and require significantly fewer messages compared to a straightforward execution of the queries. ; Presented on: Information Systems

Nowadays the wireless networks are widely spread in many civilian and military applications. The sensor networks, which are continuous developing, have to solve a lot of problems in order to ensure a reliable functionality and a reasonable lifetime. This paper presents some present issues regarding the energy preservation in wireless sensor network. Ill. 6, bibl. 7 (in English; summaries in English, Russian and Lithuanian).

The ability to operate despite failure will become increasingly important as the use of optical sensor networks grows, and the amount of sensing information to be handled by a sensor network is increasing, especially for safety and security applications. In this review, the four categories of protection to allow service to be reestablished after a failure (dedicated/shared and line/path) are thoroughly discussed. This paper also presents an overview of the most representative robust fiber-optic sensor systems, discussing their schemes, pros and cons. ; The authors are grateful to the Spanish Government project TEC2010-20224-C02-01.

A wireless sensor network (WSN) (sometimes called a wireless sensor and actuator network (WSAN) are spatially distributed autonomous sensors to monitor physical or environmental conditions,[2] such as temperature,sound,pressure,etc. and to cooperati vely pass their data through the network to a main location. The more modern networks are bi-direction al,also enabling control of sensor activity. The development of wireless sensor networks was motivat ed by military applications such as battlefield surveillance;today such networks are used in many industrial and consumer applications,such as indus trial process monitoring and control,machine health moni toring,and so on. The WSN is built of "nodes" � fr om a few to several hundreds or even thousands,where each node is connected to one (or sometimes several) sensors. Each such sensor network node has typicall y several parts:a radio transceiver with an intern al antenna or connection to an external antenna,a mic rocontroller,an electronic circuit for interfacing with the sensors and an energy source,usually a battery or an embedded form of energy harvesting. A sensor nod e might vary in size from that of a shoebox down to t he size of a grain of dust,although functioning "m otes" of genuine microscopic dimensions have yet to be cr eated. The cost of sensor nodes is similarly variab le,ranging from a few to hundreds of dollars,dependin g on the complexity of the individual sensor nodes. Size and cost constraints on sensor nodes result in corr esponding constraints on resources such as energy,memory,computational speed and communications band width. The topology of the WSNs can vary from a simple star network to an advanced multi-hop wirele ss mesh network. The propagation technique between the hops of the network can be routing or flooding The relentless development of wireless technology p aves the way to novel applications,based on sensor netw orks or wireless systems. This paper aims at bringi ng together specialists of application areas along wit h researchers ...

A wireless sensor network (WSN) (sometimes called a wireless sensor and actuator network (WSAN) are spatially distributed autonomous sensors to monitor physical or environmental conditions,[2] such as temperature, sound, pressure, etc. and to cooperatively pass their data through the network to a main location. The more modern networks are bi-directional, also enabling control of sensor activity. The development of wireless sensor networks was motivated by military applications such as battlefield surveillance; today such networks are used in many industrial and consumer applications, such as industrial process monitoring and control, machine health monitoring, and so on. The WSN is built of "nodes" – from a few to several hundreds or even thousands, where each node is connected to one (or sometimes several) sensors. Each such sensor network node has typically several parts: a radio transceiver with an internal antenna or connection to an external antenna, a microcontroller, an electronic circuit for interfacing with the sensors and an energy source, usually a battery or an embedded form of energy harvesting. A sensor node might vary in size from that of a shoebox down to the size of a grain of dust, although functioning "motes" of genuine microscopic dimensions have yet to be created.

The ability to exchange secret information is critical to many commercial, governmental, and military networks. Wireless sensor intrinsic secrecy is essential for communication confidentiality, health privacy, public safety, information superiority, and economic advantage in the modern information society. Wireless Sensor security schemes have typically evolved from those developed for traditional wire line applications, these schemes do not consider physical properties of the wireless channels. To overcome these problems, this research work develops a foundation for design and analysis of wireless sensor networks with secrecy provided by intrinsic properties such as node spatial distribution, wireless propagation medium, and aggregate network interference. This record was migrated from the OpenDepot repository service in June, 2017 before shutting down.