Dissertations / Theses on the topic 'Sensor networks'
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Farry, Michael P. (Michael Patrick). "Sensor networks for social networks." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36764.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.Includes bibliographical references (p. 51-55).
This thesis outlines the development of software that makes use of Bayesian belief networks and signal processing techniques to make meaningful inferences about real-world phenomena using data obtained from sensor networks. The effectiveness of the software is validated by applying it to the problem of detecting face-to-face social interactions between groups of people, given data readings from sensors that record light, temperature, acceleration, sound, and proximity. This application represents a novel method for social network construction which is potentially more accurate and less intrusive than traditional methods, but also more meaningful than newer methods that analyze digitally mediated communication.
by Michael P. Farry.
M.Eng.
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Karaaslan, Ibrahim. "Anti-sensor Network: Distortion-based Distributed Attack In Wireless Sensor Networks." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609276/index.pdf.
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In this thesis, a novel anti-sensor network paradigm is introduced against wireless sensor networks (WSN). Anti-sensor network (ASN) aims to destroy application reliability by adaptively and anonymously introducing adequate level of artificial distortion into the communication of the event features transported from the sensor nodes (SN) to the sink. ASN is composed of anti-sensor nodes (aSN) randomly distributed
over the sensor network field. aSNs pretend to be SNs tomaintain anonymity and so improve resiliency against attack detection and prevention mechanisms. Performance
evaluations via mathematical analysis and simulation experiments show that ASN can effectively reduce the application reliability of WSN.
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Tan, Hailun Computer Science & Engineering Faculty of Engineering UNSW. "Secure network programming in wireless sensor networks." Awarded By:University of New South Wales. Computer Science & Engineering, 2010. http://handle.unsw.edu.au/1959.4/44835.
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Network programming is one of the most important applications in Wireless Sensor Networks as It provides an efficient way to update program Images running on sensor nodes without physical access to them. Securing these updates, however, remains a challenging and important issue, given the open deployment environment of sensor nodes. Though several security schemes have been proposed to impose the authenticity and Integrity protection on network programming applications, they are either energy Inefficient as they tend to use digital signature or lacks the data confidentiality. In addition, due to the absence of secure memory management in the current sensor hardware, the attacker could inject malicious code into the program flash by exploiting buffer overflow In the memory despite the secure code dissemination. The contribution of this thesis Is to provide two software-based security protocols and one hardware-based remote attestation protocol for network programming application. Our first protocol deploys multiple one-way key chains for a multi-hop sensor network. The scheme Is shown to be lower In computational, power consumption and communication costs yet still able to secure multi??hop propagation of program images. Our second protocol utilizes an Iterative hash structure to the data packets in network programming application, ensuring the data confidentiality and authenticity. In addition, we Integrated confidentiality and DoS-attack-resistance in a multi??hop code dissemination protocol. Our final solution is a hardware-based remote attestation protocol for verification of running codes on sensor nodes. An additional piece of tamper-proof hardware, Trusted Platform Module (TPM), is imposed into the sensor nodes. It secures the sensitive information (e.g., the session key) from attackers and monitors any platform environment changes with the Internal registers. With these features of TPM, the code Injection attack could be detected and removed when the contaminated nodes are challenged in our remote attestation protocol. We implement the first two software-based protocols with Deluge as the reference network programming protocol in TinyOS, evaluate them with the extensive simulation using TOSSIM and validate the simulation results with experiments using Tmote. We implement the remote attestation protocol on Fleck, a sensor platform developed by CSIRO that Integrates an Atmel TPM chip.
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Lim, Tiong Hoo. "Dependable network protocols in wireless sensor networks." Thesis, University of York, 2013. http://etheses.whiterose.ac.uk/4903/.
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This thesis is concerned with the dependability of Wireless Sensor Networks (WSNs). We propose an approach, inspired by the immune system, that allows individual nodes to detect, diagnose and recover from different failures by switching between different protocols using a multi-modal switching mechanism. A causal link between different failures in WSN is identified. Existing fault tolerance in WSNs approaches are examined. From the survey, it is identified that various attempts have been made to improve the fault tolerance of the communication protocol especially in the routing protocols. Although tests have been performed to evaluate the communication protocols prior to deployment, failures in WSNs are still being reported when deployed in real environments. A Systematic Protocol Evaluation Technique (SPET) is proposed and applied to evaluate the dependability of the proposed multi-modal protocol and reduce the uncertainties in the experiment and to demonstrate the confidence in the measurements taken from experiments.
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KHAN, SARMAD ULLAH. "Key Management in Wireless Sensor Networks, IP-Based Sensor Networks, Content Centric Networks." Doctoral thesis, Politecnico di Torino, 2013. http://hdl.handle.net/11583/2506342.
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Cryptographic keys and their management in network communication is considered the main building block of security over which other security primitives are based. These cryptographic keys ensure the privacy, authentication, integrity and non-repudiation of messages. However, the use of these cryptographic keys and their management in dealing with the resource constrained devices (i.e. Sensor nodes) is a challenging task.
A number of key management schemes have been introduced by researchers all over the world for such resource constrained networks. For example, light weight PKI and elliptic curve cryptography schemes are computationally expensive for these resource constrained devices. So far the symmetric key approach is considered best for these constrained networks and different variants of it been developed for these networks (i.e. probabilistic key distribution approach). The probabilistic key distribution approach consumes less memory than the standard symmetric key approach but it suffers from the connectivity issues (i.e. the connectivity depends on the common shared keys between the nodes).
Most of those schemes were proposed by considering static sensor networks (e.g. Industrial process monitoring, Environmental monitoring, movement detection in military applications, forests etc.). However, the use of these existing key management schemes for mobile wireless sensor networks applications introduces more challenges in terms of network connectivity, energy consumption, memory cost, communication overhead and protection of key materials against some well known attacks. Keeping these challenges in mind, previous research has proposed some key management schemes considering the mobility scenarios in ad hoc networks and wireless sensor networks (e.g. vehicular networks, health monitoring systems).However these schemes consume more resource because of a much higher communication packet exchange during the handover phase for the authentication of joining and leaving nodes than the static networks where there is no extra communication for the handover and authentication.
The motivation of this research work is to investigate and propose new algorithms not only to improve the efficiency of these existing authentication and key management schemes in terms of connectivity, memory and security by considering the mobility scenario in wireless sensor networks, but also to develop new algorithms that suit these constrained networks than the existing schemes.
First, we choose the existing key pool approach for authentication and key management and improve its network connectivity and resilience against some well known attacks (e.g. node capturing attacks) while reduce the memory cost by storing those key pools in each sensor node. In the proposed solution, we have divided the main key pool into two virtual mutually exclusive key pools. This division and constructing a key from two chosen keys, one from each key pool, helps to reduce the memory cost of each node by assigning fewer keys for the same level of network connectivity as the existing key pool frameworks.
Although, the proposed key pool approach increases the network resilience against node compromission attacks because of the smaller number of keys assigned to each node, however it does not completely nullify the effect of the attacks. Hence we proposed an online mutual authentication and key establishment and management scheme for sensor networks that provides almost 100\% network connectivity and also nullifies the effect of node compromission attacks. In the proposed online key generation approach, the secret key is dependent on both communicating parties. Once the two communicating parties authenticate each other, they would successfully establish a secret communication key, otherwise they stop communication and inform the network manager about the intruder detection and activity.
The last part of the thesis considers the integration of two different technologies (i.e. wireless sensor networks and IP networks). This is a very interesting and demanding research area because of its numerous applications, such as smart energy, smart city etc.. However the security requirements of these two kind of networks (resource constrained and resourceful) make key management a challenging task. Hence we use an online key generation approach using elliptic curve cryptography which gives the same security level as the standard PKI approach used in IP networks with smaller key length and is suited for the sensor network packet size limitations. It also uses a less computationally expensive approach than PKI and hence makes ECC suitable to be adopted in wireless sensor networks. In the key management scheme for IP based sensor networks, we generate the public private key pair based on ECC for each individual sensor node. However the public key is not only dependent on the node's parameter but also the parameters of the network to which it belongs. This increases the security of the proposed solution and avoids intruders pretending to be authentic members of the network(s) by spreading their own public keys.
In the last part of the thesis we consider Content Centric Networking (CCN) which is a new routing architecture for the internet of the future. Building on the observation that today's communications are more oriented towards content retrieval (web, P2P, etc.) than point-to-point communications (VoIP, IM, etc.), CCN proposes a radical revision of the Internet architecture switching from named hosts (TCP/IP protocols) to named data to best match its current usage. In a nutshell, content is addressable, routable, self-sufficient and authenticated, while locations no longer matter. Data is seen and identified directly by a routable name instead of a location (the address of the server). Consequently, data is directly requested at the network level not from its holder, hence there is no need for the DNS). To improve content diffusion, CCN relies on data distribution and duplication, because storage is cheaper than bandwidth: every content - particularly popular one - can be replicated and stored on any CCN node, even untrustworthy. People looking for particular content can securely retrieve it in a P2P-way from the best locations available.
So far, there has been little investigation of the security of CCNs and there is no specific key management scheme for that. We propose an authentication and key establishment scheme for CCNs in which the contents are authenticated by the content generating node, using pre-distributed shares of encryption keys. The content requesting node can get those shares from any node in the network, even from malicious and intruder ones, in accordance with a key concept of CCNs. In our work we also provide means to protect the distributed shares from modification by these malicious/intruder nodes. The proposed scheme is again an online key generation approach but including a relation between the content and its encryption key. This dependency prevents the attackers from modifying the packet or the key shares.
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Chaves, Andrea, Bruno Mayoral, Hyun-Jin Park, Mark Tsang, and Sean Tunell. "Wireless Sensor Networks: A Grocery Store Application." International Foundation for Telemetering, 2008. http://hdl.handle.net/10150/606223.
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ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, CaliforniaThis paper explains the development of a wireless network system implemented to streamline grocery store checkout procedures. The design employs a wireless telemetry network consisting of a base station and wireless motes (Micaz MPR2400) that will be located on certain aisles, and attached to shopping carts. This system allows customers to scan items while they shop and uses cashiers for payment purposes only. The objective is to minimize the amount of processing performed by cashiers in order to reduce waiting times in line. The system was tested in a simulation environment and waiting times were reduced by 65%.
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Sevgi, Cuneyt. "Network Dimensioning In Randomly Deployed Wireless Sensor Networks." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12611213/index.pdf.
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In this study, we considered a heterogeneous, clustered WSN, which consists of two
types of nodes (clusterheads and sensor nodes) deployed randomly over a sensing field.
We investigated two cases based on how clusterheads can reach the sink: direct and
multi-hop communication cases. Network dimensioning problems in randomly deployed
WSNs are among the most challenging ones as the attributes of these networks are
mostly non-deterministic. We focused on a number of network dimensioning problems
based on the connected coverage concept, which is the degree of coverage achieved by
only the connected devices. To evaluate connected coverage, we introduced the term
cluster size, which is the expected value of the area covered by a clusterhead together
with sensor nodes connected to it. We derived formulas for the cluster size and validated
them by computer simulations. By using the cluster size formulas, we proposed
a method to dimension a WSN for given targeted connected coverage.
Furthermore, we formulated cost optimization problems for direct and multi-hop
communication cases. These formulations utilize not only cluster size formulas but also
the well-connectivity concept. We suggested some search heuristics to solve these optimization
problems. Additionally, we justified that, in practical cases, node heterogeneity
can provide lower cost solutions. We also investigated the lifetime of WSNs and for
mulated a cost optimization problem with connected coverage and lifetime constraints.
By solving this optimization problem, one can determine the number of nodes of each
type and the initial energies of each type of node that leads to lowest cost solution while
satisfying the minimum connected coverage and minimum lifetime requirements.
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Yuan, Fenghua. "Lightweight network management design for wireless sensor networks." Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Fall2007/F_Yuan_081307.pdf.
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Teo, Hong-Siang. "Security of sensor networks." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Jun%5FTeo.pdf.
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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, June 2006.Thesis Advisor(s): John McEachen. "June 2006." Includes bibliographical references (p. 49-51). Also available in print.
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Yazar, Dogan. "RESTful Wireless Sensor Networks." Thesis, Uppsala University, Department of Information Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-110353.
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Sensor networks have diverse structures and generally employ proprietary protocols to gather useful information about the physical world. This diversity generates problems to interact with these sensors since custom APIs are needed which are tedious, error prone and have steep learning curve. In this thesis, I present RESThing, a lightweight REST framework for wireless sensor networks to ease the process of interacting with these sensors by making them accessible over the Web. I evaluate the system and show that it is feasible to support widely used and standard Web protocols in wireless sensor networks. Being able to integrate these tiny devices seamlessly into the global information medium, we can achieve the Web of Things.
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Finne, Niclas. "Towards adaptive sensor networks." Licentiate thesis, Uppsala universitet, Avdelningen för datorteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-227617.
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Wireless sensor networks consist of many small embedded devices that are equipped with sensors and a wireless communication unit. These devices, or sensor nodes, are typically low cost, resource constrained and battery-powered. Sensor network applications include environmental monitoring, industrial condition monitoring, building surveillance, and intelligent homes. Sensor network applications today are often developed either using standard software components which enables simpler development but leads to far from optimal performance, or software customized for the specific application which complicates development, software updates, and software reuse. We suggest that logic is separated from configuration and other information, for instance, network statistics and estimated power consumption. Software components publish their configuration and other information using a generalized programming abstraction. Configuration policies are separate modules that react on changes and reconfigure the sensor node as needed. These configuration policies are responsible for coordinating the configuration between the components and optimize the sensor network towards the application objectives. One of our contributions is that we demonstrate the need for self-monitoring and self-configuration based on experiences from two deployed sensor networks. Our main contribution is that we devise a configuration architecture that solves the problem of cross-layer optimization for sensor network applications without tight coupling between components, thus enabling standard and easily replaceable components to be used. The configuration architecture makes it possible to reach the same level of performance as specialized cross-layer optimizations but without adding application-specific knowledge to the components.WISENET
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Munishwar, Vikram P. "Storage and indexing issues in sensor networks." Diss., Online access via UMI:, 2006.
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Jones, Peter B. (Peter B. ). S. M. Massachusetts Institute of Technology. "Dynamic sensor tasking in heterogeneous, mobile sensor networks." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/35782.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.Includes bibliographical references (leaves 97-101).
Modern sensor environments often attempt to combine several sensors into a single sensor network. The nodes of this network are generally heterogeneous and may vary with respect to sensor complexity, sensor operational modes, power costs and other salient features. Optimization in this environment requires considering all possible sensor modalities and combinations. Additionally, in many cases there may be a time critical objective, requiring sensor plans to be developed and refined in real-time. This research will examine and expand on previous work in multi-sensor dynamic scheduling, focusing on the issue of near optimal sensor-scheduling for real-time detection in highly heterogeneous networks. First, the issue of minimum time inference is formulated as a constrained optimization problem. The principles of dynamic programming are applied to the problem. A network model is adopted in which a single "leader" node makes a sensor measurement. After the measurement is made, the leader node chooses a successor (or chooses to retain network leadership). This model leads to an index rule for leader/action selection under which the leader is the sensor node with maximum expected rate of information acquisition. In effect, the sensor and modality with the maximum ratio of expected entropic decrease to measurement time is shown to be an optimal choice for leader.
(cont.) The model is then generalized to include networks with simultaneously active sensors. In this case the corresponding optimization problem becomes prohibitively difficult to solve, and so a game theoretic approach is adopted in order to balance the preferences of the several sensors in the network. A novel algorithm for multiplayer coordination is developed that uses iterative partial utility revelation to achieve bounded Pareto inefficiency of the solution.
by Peter Jones.
S.M.
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Firouzi, Fereshteh. "Sensor Placement for Damage Localization in Sensor Networks." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/6019.
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The objective of this thesis is to formulate and solve the sensor placement problem for damage localization in a sensor network. A Bayesian estimation problem is formulated with the time-of-flight (ToF) measurements. In this model, ToF of lamb waves, which are generated and received by piezoelectric sensors, is the total time for each wave to be transmitted, reflected by the target, and received by the sensor. The ToF of the scattered lamb wave has characteristic information about the target location. By using the measurement model and prior information, the target location is estimated in a centralized sensor network with a Monte Carlo approach. Then we derive the Bayesian Fisher information matrix (B-FIM) and based on that posterior Cramer-Rao lower bound (PCRLB), which sets a limit on the mean squared error (MSE) of any Bayesian estimator. In addition, we develop an optimal sensor placement approach to achieve more accurate damage localization, which is based on minimizing the PCRLB. Simulation results show that the optimal sensor placement solutions lead to much lower estimation errors than some sub-optimal sensor placement solutions.
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She, Huimin. "Network-Calculus-based Performance Analysis for Wireless Sensor Networks." Licentiate thesis, KTH, Electronic, Computer and Software Systems, ECS, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10686.
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Recently, wireless sensor network (WSN) has become a promising technologywith a wide range of applications such as supply chain monitoringand environment surveillance. It is typically composed of multiple tiny devicesequipped with limited sensing, computing and wireless communicationcapabilities. Design of such networks presents several technique challengeswhile dealing with various requirements and diverse constraints. Performanceanalysis techniques are required to provide insight on design parametersand system behaviors.
Based on network calculus, we present a deterministic analysis methodfor evaluating the worst-case delay and buffer cost of sensor networks. Tothis end, three general traffic flow operators are proposed and their delayand buffer bounds are derived. These operators can be used in combinationto model any complex traffic flowing scenarios. Furthermore, the methodintegrates a variable duty cycle to allow the sensor nodes to operate at lowrates thus saving power. In an attempt to balance traffic load and improveresource utilization and performance, traffic splitting mechanisms areintroduced for mesh sensor networks. Based on network calculus, the delayand buffer bounds are derived in non-splitting and splitting scenarios.In addition, analysis of traffic splitting mechanisms are extended to sensornetworks with general topologies. To provide reliable data delivery in sensornetworks, retransmission has been adopted as one of the most popularschemes. We propose an analytical method to evaluate the maximum datatransmission delay and energy consumption of two types of retransmissionschemes: hop-by-hop retransmission and end-to-end retransmission.
We perform a case study of using sensor networks for a fresh food trackingsystem. Several experiments are carried out in the Omnet++ simulationenvironment. In order to validate the tightness of the two bounds obtainedby the analysis method, the simulation results and analytical results arecompared in the chain and mesh scenarios with various input traffic loads.From the results, we show that the analytic bounds are correct and tight.Therefore, network calculus is useful and accurate for performance analysisof wireless sensor network.
Ipack VINN Excellence Center
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Samarasinghe, Kasun. "Network Coding with Limited Overhearing in Wireless Sensor Networks." Thesis, KTH, Kommunikationsnät, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-53518.
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Network Coding as a recently emerged concept in Communication Networks Research, has attracted a lot of attention in networking research community. Previous research on applying Network Coding in Wireless Sensor Networks, do not consider most crucial constraints inherent to sensor networks. Especially most of them assume overhearing of neighboring transmissions for free, which is unrealistic in practical sensor network environments where nodes have limited energy. Therefore these applications fail to make an impact on real world sensor network deployments. In some sensor networking scenarios it is possible to manipulate overhearing in a controlled manner. In this research we apply network coding in to improve throughput of a Time Division Multiple Access(TDMA) based Medium Access Control(MAC) protocol called GINMAC , manipulating overhearing appropriately. Our results show that network coding can improve the throughput while trading owith other network performance characteristics like reliability and power consumption.
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Al-Hoqani, Noura Y. S. "In-network database query processing for wireless sensor networks." Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/36226.
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In the past research, smart sensor devices have become mature enough for large, distributed networks of such sensors to start to be deployed. Such networks can include tens or hundreds of independent nodes that can perform their functions without human interactions such as recharging of batteries, the configuration of network routes and others. Each of the sensors in the wireless sensor network is considered as microsystem, which consists of memory, processor, transducers and low bandwidth as well as a low range radio transceiver. This study investigates an adaptive sampling strategy for WSS aimed at reducing the number of data samples by sensing data only when a significant change in these processes is detected. This detection strategy is based on an extension to Holt's Method and statistical model. To investigate this strategy, the water consumption in a household is used as a case study. A query distribution approach is proposed, which is presented in detail in chapter 5. Our developed wireless sensor query engine is programmed on Sensinode testbed cc2430. The implemented model used on the wireless sensor platform and the architecture of the model is presented in chapters six, seven, and eight. This thesis presents a contribution by designing the experimental simulation setup and by developing the required database interface GUI sensing system, which enables the end user to send the inquiries to the sensor s network whenever needed, the On-Demand Query Sensing system ODQS is enhanced with a probabilistic model for the purpose of sensing only when the system is insufficient to answer the user queries. Moreover, a dynamic aggregation methodology is integrated so as to make the system more adaptive to query message costs. Dynamic on-demand approach for aggregated queries is implemented, based in a wireless sensor network by integrating the dynamic programming technique for the most optimal query decision, the optimality factor in our experiment is the query cost. In-network query processing of wireless sensor networks is discussed in detail in order to develop a more energy efficient approach to query processing. Initially, a survey of the research on existing WSN query processing approaches is presented. Building on this background, novel primary achievements includes an adaptive sampling mechanism and a dynamic query optimiser. These new approaches are extremely helpful when existing statistics are not sufficient to generate an optimal plan. There are two distinct aspects in query processing optimisation; query dynamic adaptive plans, which focus on improving the initial execution of a query, and dynamic adaptive statistics, which provide the best query execution plan to improve subsequent executions of the aggregation of on-demand queries requested by multiple end-users. In-network query processing is attractive to researchers developing user-friendly sensing systems. Since the sensors are a limited resource and battery powered devices, more robust features are recommended to limit the communication access to the sensor nodes in order to maximise the sensor lifetime. For this reason, a new architecture that combines a probability modelling technique with dynamic programming (DP) query processing to optimise the communication cost of queries is proposed. In this thesis, a dynamic technique to enhance the query engine for the interactive sensing system interface is developed. The probability technique is responsible for reducing communication costs for each query executed outside the wireless sensor networks. As remote sensors have limited resources and rely on battery power, control strategies should limit communication access to sensor nodes to maximise battery life. We propose an energy-efficient data acquisition system to extend the battery life of nodes in wireless sensor networks. The system considers a graph-based network structure, evaluates multiple query execution plans, and selects the best plan with the lowest cost obtained from an energy consumption model. Also, a genetic algorithm is used to analyse the performance of the approach. Experimental testing are provided to demonstrate the proposed on-demand sensing system capabilities to successfully predict the query answer injected by the on-demand sensing system end-user based-on a sensor network architecture and input query statement attributes and the query engine ability to determine the best and close to the optimal execution plan, given specific constraints of these query attributes . As a result of the above, the thesis contributes to the state-of-art in a network distributed wireless sensor network query design, implementation, analysis, evaluation, performance and optimisation.
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Spinden, David, Jeffrey Jasper, and Kurt Kosbar. "Comparison of Wireless Ad-Hoc Sensor Networks." International Foundation for Telemetering, 2004. http://hdl.handle.net/10150/605786.
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International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, CaliforniaThere are a number of telemetry applications where it would be helpful to have networks of sensors that could autonomously discover their connectivity, and dynamically reconfigure themselves during use. A number of research groups have developed wireless ad-hoc sensor network systems. This paper reviews the state-of-the-art in wireless ad-hoc networks, examining the features, assumptions, limitations and unique attributes of some of the more popular solutions to this problem.
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Molineux, Jeffrey S. "Integration of Wireless Sensor Networks Into a Commercial Off-the-Shelf (COTS) Multimedia Network." Thesis, Monterey, California: Naval Postgraduate School, 2012.
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As the primary military operating environment shifts from the traditional battlefields to a more diverse urban environment, the use of remote wireless sensors is increasing. Traditional development and procurement methods are not capable of meeting the changing requirements and time constraints of commanders. To minimize the time to develop and deploy new systems, commercial solutions must be examined. The focus of this thesis is on the integration of Commercial Off-the-Shelf (COTS) components into a wireless multimedia sensor network. Because components from multiple vendors were utilized, different operating systems and transmission protocols had to be integrated across the network. The network must be capable of providing a varying Quality of Service (QoS) level depending on the active sensors in the network. To ensure the QoS level is met, an adaptive QoS algorithm was implemented in the wireless IEEE 802.11 router which monitored and measured the outgoing transmission interface; from which, it determined the latency and transmission jitter. Based on the results, the program can adjust the bandwidth as necessary. Finally, a user interface is developed that allows end users to monitor the network. The performance of the network is based on the end-to-end throughput, latency and jitter exhibited by the network.
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Ould-Ahmed-Vall, ElMoustapha. "Algorithms for Self-Organizing Wireless Sensor Networks." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14473.
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The unique characteristics of sensor networks pose numerous challenges that have to be overcome to enable their efficient use. In particular, sensor networks are energy constrained because of their reliance on battery power. They can be composed of a large number of unreliable nodes. These characteristics render node collaboration essential to the accomplishment of the network task and justify the development of new algorithms to provide services such as routing, fault tolerance and naming.
This work increases the knowledge on the growing field of sensor network algorithms by contributing a new evaluation tool and two new algorithms.
A new sensor network simulator that can be used to evaluate sensor network algorithms is discussed. It incorporates models for the different functional units composing a sensor node and characterizes the energy consumption of each. It is designed in a modular and efficient way favoring the ease of use and extension. It allows the user to choose from different implementations of energy models, accuracy models and types of sensors.
The second contribution of this thesis is a distributed algorithm to solve the unique ID assignment problem in sensor networks. Our solution starts by assigning long unique IDs and organizing nodes in a tree structure. This tree structure is used to compute the size of the network. Then, unique IDs are assigned using the minimum length. Globally unique IDs are useful in providing many network functions, e.g. node maintenance and security. Theoretical and simulation analysis of the ID assignment algorithm demonstrate that a high percentage of nodes are assigned unique IDs at the termination of the algorithm when the algorithm parameters are set properly. Furthermore, the algorithm terminates in a short time that scales well with the network size.
The third contribution of this thesis is a general fault-tolerant event detection scheme that allows nodes to detect erroneous local decisions based on the local decisions reported by their neighbors. It can handle cases where nodes have different and dynamic accuracy levels. We prove analytically that the derived fault-tolerant estimator is optimal under the maximum a posteriori criterion. An equivalent weighted voting scheme is derived.
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Hasir, Ibrahim. "The Effect of Mobility on Wireless Sensor Networks." Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc699868/.
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Wireless sensor networks (WSNs) have gained attention in recent years with the proliferation of the micro-electro-mechanical systems, which has led to the development of smart sensors. Smart sensors has brought WSNs under the spotlight and has created numerous different areas of research such as; energy consumption, convergence, network structures, deployment methods, time delay, and communication protocols. Convergence rates associated with information propagations of the networks will be questioned in this thesis. Mobility is an expensive process in terms of the associated energy costs. In a sensor network, mobility has significant overhead in terms of closing old connections and creating new connections as mobile sensor nodes move from one location to another. Despite these drawbacks, mobility helps a sensor network reach an agreement more quickly. Adding few mobile nodes to an otherwise static network will significantly improve the network’s ability to reach consensus. This paper shows the effect of the mobility on convergence rate of the wireless sensor networks, through Eigenvalue analysis, modeling and simulation.
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Kumar, Rajnish. "Adaptable Protocol Stack for Future Sensor Networks." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/13931.
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The goal of this thesis is to provide an adaptable protocol stack
architecture for data fusion applications. Towards the goal, this
thesis presents the design of SensorStack, that addresses three key
issues. First, towards network-level adaptability, how to
dynamically adapt the placement of a fusion application task graph
on the network? We have designed a distributed role assignment
algorithm and implemented in the context of DFuse, a framework for
distributed data fusion. Second, towards node-level adaptability,
how to facilitate cross-layering on a node to foster agile
adaptation of a node's behavior commensurate with the network-level
changes? SensorStack provides information exchange service (IES) as
a framework for cross-module information exchange. Finally, towards
tying the network and node level adaptability together, control data
published in IES needs to be shared across the network. SensorStack
uses a probabilistic broadcast based dissemination service (IDS) for
control data. We implement SensorStack in TinyOS and Linux to
validate the SensorStack design, and use simulation experiments to
investigate its network performance. Experiments demonstrate the
utility of adaptability in SensorStack to increase application
longevity.
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Patterson, Robert Matthew. "Self-Calibration of Sensor Networks." Connect to this title online, 2002. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1023465547.
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Al-Khateeb, Shadi A. "Fire Detection Using Wireless Sensor Networks." Youngstown State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1411471850.
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Dogru, Sedat. "Sycophant Wireless Sensor Networks Tracked By Sparsemobile Wireless Sensor Networks While Cooperativelymapping An Area." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615139/index.pdf.
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In this thesis the novel concept of Sycophant Wireless Sensors (SWS) is introduced. A SWS network is a static ectoparasitic clandestine sensor network mounted incognito on a mobile agent using only the agent&rsquos mobility without intervention. SWS networks not only communicate with each other through mobileWireless Sensor Networks (WSN) but also cooperate with them to form a global hybrid Wireless Sensor Network. Such a hybrid network has its own problems and opportunities, some of which have been studied in this thesis work. Assuming that direct position measurements are not always feasible tracking performance of the sycophant using range only measurements for various communication intervals is studied. Then this framework was used to create a hybrid 2D map of the environment utilizing the capabilities of the mobile network the sycophant. In order to show possible applications of a sycophant deployment, the sycophant sensor node was equipped with a laser ranger as its sensor, and it was let to create a 2D map of its environment. This 2D map, which corresponds to a height dierent than the follower network, was merged with the 2D map of the mobile network forming a novel rough 3D map. Then by giving up from the need to properly localize the sycophant even when it is disconnected to the rest of the network, a full 3D map of the environment is obtained by fusing 2D map and tracking capabilities of the mobile network with the 2D vertical scans of the environment by the sycophant. And finally connectivity problems that arise from the hybrid sensor/actuator network were solved. For this 2 new connectivity maintenance algorithms, one based on the helix structures of the proteins, and the other based on the acute triangulation of the space forming a Gabriel Graph, were introduced. In this new algorithms emphasis has been given to sparseness in order to increase fault tolerance to regional problems. To better asses sparseness a new measure, called Resistance was introduced, as well as another called updistance.
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Al-Mousa, Yamin Samir. "MAC/routing design for under water sensor networks /." Online version of thesis, 2007. http://hdl.handle.net/1850/4496.
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Paturu, Raghunatha Rao Nityananda Suresh. "Path Planning under Failures in Wireless Sensor Networks." Thesis, North Dakota State University, 2013. http://hdl.handle.net/10365/22971.
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This paper explores how an all pair shortest path can be obtained in a wireless sensor network when sensors fail. Sensors are randomly deployed in a predefined geographical area, simulating the deployment of sensors from an airplane, and finding shortest path between all the sensors deployed based on distance. A major problem to address in wireless sensor networks is the impact of sensor failures on existing shortest paths in the network. An application is developed to simulate a network and find shortest paths affected by a sensor failure and find alternative shortest path. When a sensor fails, all the shortest paths and all the remaining sensors in the network are checked to see if the sensor failure has any impact on the network. Alternative shortest path is calculated for those paths affected by sensor failures.
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Barragan, Dante E. "Optimal placement of sensors for network lifetime extension in wireless sensor networks with dynamic routing." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Nune, Raju. "Simulink® Based Design and Implementation of Wireless Sensor Networks." Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc1062869/.
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A wireless sensor network (WSN) is a spatially distributed network used to monitor the physical and environmental conditions such as temperature, pressure, sound, humidity, heat, etc. WSNs can be modeled using different simulation frameworks like OMNeT++, Prowler, Atarraya, PiccSIM, Network Simulator, etc. In this research, Simulink framework was used to model WSN system. The complete WSN consisting of transmitting nodes, communication channel, and receiver nodes are built in the Simulink framework. Orthogonal frequency division multiplexing technique was used to transmit the information. The implemented wireless sensor system behavior is studied using temperature as the measurement parameter at different values of signal to noise ratio. The plots of bit error rate versus signal to noise ratio and frame error rate versus signal to noise ratio are generated in the Simulink framework. It is easy to study the effect of different physical layer parameters on the performance of wireless sensor networks by implementing WSN in the Simulink framework.
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Ogunlu, Bilal. "Lifetime Analysis For Wireless Sensor Networks." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605226/index.pdf.
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Sensor technologies are vital today in gathering information about certain environments and wireless sensor networks are getting more widespread use everyday. These networks are characterized by a number of sensor nodes deployed in the field for the observation of some phenomena. Due to the limited battery capacity in sensor nodes, energy efficiency is a major and challenging problem in such power-constrained networks. Some of the network design parameters have a direct impact on the network&rsquos lifetime. These parameters have to be chosen in such a way that the network use its energy resources efficiently. This thesis studies these parameters that should be selected according to certain trade offs with respect to the network&rsquo
s lifetime. In this work, these trade offs have been investigated and illustrated in detail in various combinations. To achieve this goal, a special simulation tool has been designed and implemented in this work that helps in analyzing the effects of the selected parameters on sensor network&rsquo
s lifetime. OMNeT++, a discrete event simulator, provides the framework for the sensor network simulator&rsquo
s development. Ultimately, results of extensive computational tests are presented, which may be helpful in guiding the sensor network designers in optimally selecting the network parameters for prolonged lifetime.
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Lin, Erwei Kam Moshe. "Detection in distributed sensor networks /." Philadelphia, Pa. : Drexel University, 2005. http://hdl.handle.net/1860/1303.
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Gao, Huaien. "Distributed learning in sensor networks." Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-96120.
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Chraibi, Youssef. "Localization in Wireless Sensor Networks." Thesis, KTH, Reglerteknik, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-107528.
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Similar to many technological developments, wireless sensor networks have emerged from military needs and found its way into civil applications. Today, wireless sensor networks has become a key technology for different types of ”smart environments”, and an intense research effort is currently underway to enable the application of wireless sensor networks for a wide rangeof industrial problems. Wireless networks are of particular importance whena large number of sensor nodes have to be deployed, and/or in hazardous situations. Localization is important when there is an uncertainty of the exact location of some fixed or mobile devices. One example has been in the supervision of humidity and temperature in forests and/or fields, where thousands of sensors are deployed by a plane, giving the operator little or no possibility to influence the precise location of each node. An effective localization algorithm can then use all the available information from the wireless sensor nodes to infer the position of the individual devices. Another application is the positioning of a mobile robot based on received signal strength from a set of radio beacons placed at known locations on the factory floor. This thesis work is carried out on the wireless automation testbed at the S3. Focusing on localization processes, we will first give an overview of the state of the art in this area. From the various techniques, one idea was found to have significant bearing for the development of a new algorithm. We present analysis and simulations of the algorithms, demonstrating improved accuracy compared to other schemes although the accuracy is probably not good enough for some high-end applications. A third aspect of the work concerns the feasibility of approaches based on received signal strength indication (RSSI). Multiple measurement series have been collected in the lab with the MoteIV wireless sensor node platform. The measurement campaign indicates significant fluctuations in the RSSI values due to interference and limited repeatability of experiments, which may limit the reliability of many localization schemes, especially in an indoor environment.
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Pinto, Luis Ramos. "Aerial Multi-hop Sensor Networks." Research Showcase @ CMU, 2018. http://repository.cmu.edu/dissertations/1180.
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Unmanned Aerial Vehicles (UAVs) recently enabled a myriad of new applications spanning domains from personal entertainment and industrial inspection, to criminal surveillance and forest monitoring. A combination of sensor collection, wireless communication and path planning between multiple distributed agents is the natural way to support applications. Several small UAVs working collaboratively can rapidly provide extended reach, at low cost, and efficiently stream sensor information to operators on a ground station. A significant amount of previous work has addressed each of these topics independently, but in this dissertation we propose a holistic approach for joint coordination of networking and topology (placement of mobile nodes). Our thesis is that this approach improves user-interactive control of UAVs for live-streaming applications in terms of throughput, delay and reliability. In order to defend these claims, this dissertation begins by experimentally evaluating and modeling the wireless link between two UAVs, under different conditions. Due to limited link range, and the need for wide-area operation, the model is extended to encompass a multi-hop topology. We show that the performance of such networks using COTS devices is typically poor, and solutions must rely on coordination of network protocol and topology, simultaneously. At the network layer, we introduce a novel Time-division Multiple Access (TDMA) scheme called Distributed Variable Slot Protocol that relies on adaptive slot-length. We prove its convergence as well as its meliorated performance experimentally validated, namely 50% higher packet delivery. In terms of network topology, we show that without node placement control overall performance of the network is severely penalized, due to natural link asymmetries. We propose a novel protocol, named Dynamic Relay Placement, that is able to do both online link quality model-estimation and in a distributed fashion decide the best location for each network node, increasing throughput by 300%. Finally, we demonstrate the end-to-end system in a multi-vehicle monitoring mission. We show that coordination of multiple UAVs increases the sensor sampling rate up to 7 times in wide areas when compared to a naive approach. This work considers environmental constraints such as wind, as well as the intrinsic limitations of the vehicles such as maximum acceleration.
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Xue, Wenwei. "Event detection for sensor networks /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?CSED%202007%20XUE.
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Chiang, Mu-Huan. "Energy optimization in sensor networks." Saarbrücken VDM Verlag Dr. Müller, 2007. http://www.lib.ncsu.edu/theses/available/etd-11022007-115419/unrestricted/etd.pdf.
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Cao, Hui. "Stabilization in wireless sensor networks." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1211079872.
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Sandberg, Henrik, Maben Rabi, Mikael Skoglund, and Karl Henrik Johansson. "Estimation over heterogeneous sensor networks." KTH, ACCESS Linnaeus Centre, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-30325.
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Design trade-offs between estimation performance, processing delay and communication cost for a sensor scheduling problem is discussed. We consider a heterogeneous sensor network with two types of sensors: the first type has low-quality measurements, small processing delay and a light communication cost, while the second type is of high quality, but imposes a large processing delay and a high communication cost. Such a heterogeneous sensor network is common in applications, where for instance in a localization system the poor sensor can be an ultrasound sensor while the more powerful sensor can be a camera. Using a time-periodic Kalman filter, we show how one can find an optimal schedule of the sensor communication. One can significantly improve estimation quality by only using the expensive sensor rarely. We also demonstrate how simple sensor switching rules based on the Riccati equation drives the filter into a stable time-periodic Kalman filter. ￜ 2008 IEEE.QC 20110224
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Tseng, Kuan-Chieh Robert. "Resilience of wireless sensor networks." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/33713.
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The coverage of a wireless sensor network is a measure of the quality of service. One type of coverage is k-barrier coverage. Given a starting region S and an ending region T , we say that a sensor network has k-barrier coverage with respect to S and T if any S−T path in the surveillance domain must intersect the coverage regions of at least k sensors.
In this thesis, we focus on determining the resilience of a wireless sensor network. The resilience is defined to be the minimum number of sensors that need to be removed in order to ensure the existence of a S−T path that does not cross any sensor coverage region. A sensor network with resilience k constitutes a k-barrier coverage.
We demonstrate that determining resilience of a wireless sensor network with 2D surveillance domain is NP-hard for the case when the sensor coverage regions are unit line segments. Furthermore, it is possible to extend the reduction to show that the problem remains NP-hard for other types of sensor coverage regions. In general, if the shape of the coverage region is non-symmetric, then determining resilience is NP-hard.
We also investigate the problem of determining resilience of a wireless sensor network with 3D surveillance domain. In this case, we show that if the coverage regions of the sensors are unit spheres, then the problem is NP-hard.
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Devici, Dogukan. "Consensus performance in sensor networks." Thesis, KTH, Kommunikationsnät, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-132186.
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Saif, Waleed Abdulwahed. "Localization in wireless sensor networks." Thesis, University of Leeds, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.555845.
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In this thesis we examine localization in wireless sensor networks starting with a brief overview of the basics of radiolocation techniques and then look at some of the most well-known commercial positioning techniques and localization algorithms. We then concentrate on the application of the Fastmap (FM) algorithm in the field of wireless sensor localization. Our first contribution in this thesis is the mathematical analysis of the FM algorithm in terms of the mean squared error (MSE) of the coordinate estimate under a multiplicative noise model followed by the optimum placement of anchor nodes. The algorithm is compared to Linear Least Squares (LLS) algorithm, which is well known and has a similar complexity to that of FM. Another contribution is proposing the angle-projected FM algorithm for wireless sensor nodes localization in order to enhance the connectivity of the network and the overall performance. A comprehensive study and mathematical analysis in terms of the MSE for this algorithm is presented and it is also compared with the original FM algorithm. We also propose a weighted Fastmap (WFM) algorithm in which more than one pair of anchor nodes is used to evaluate the first coordinate (i.e., x-coordinate) of the unknown nodes in order to reduce the effect of error dependency in the y-coordinate estimation. (In the original FM algorithm only one pair of anchor nodes was employed.) The optimal WFM weights are determined via (constrained) minimization of the MSE of the estimated node coordinates. A simplification of the WFM is also introduced, called the averaged FM (AFM), where complexity is reduced at the expense of degradation in the overall WFM performance. Both the WFM and AFM exhibit improved performance over the original FM algorithm. Finally, an unbiased version of the WFM, AFM and FM is presented in which an estimate of the bias term is removed to improve the overall MSE performance. The effect of this modification on the algorithms' performance is then analysed and discussed.
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Li, Wei. "Cooperation arrayed wireless sensor networks." Thesis, Imperial College London, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.536033.
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Peng, Wei. "Optimisation of wireless sensor networks." Thesis, University of Oxford, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.543734.
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Cheng, King-yip, and 鄭勁業. "Localization in wireless sensor networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B38700189.
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Yordanova, Veronika. "Intelligent adaptive underwater sensor networks." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10042482/.
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Autonomous Underwater Vehicle (AUV) technology has reached a sufficient maturity level to be considered a suitable alternative to conventional Mine Countermeasures (MCM). Advantages of using a network of AUVs include time and cost efficiency, no personnel in the minefield, and better data collection. A major limitation for underwater robotic networks is the poor communication channel. Currently, acoustics provides the only means to send messages beyond a few metres in shallow water, however the bandwidth and data rate are low, and there are disturbances, such as multipath and variable channel delays, making the communication non-reliable. The solution this thesis proposes using a network of AUVs for MCM is the Synchronous Rendezvous (SR) method --- dynamically scheduling meeting points during the mission so the vehicles can share data and adapt their future actions according to the newly acquired information. Bringing the vehicles together provides a robust way of exchanging messages, as well as means for regular system monitoring by an operator. The gains and losses of the SR approach are evaluated against a benchmark scenario of vehicles having their tasks fixed. The numerical simulation results show the advantage of the SR method in handling emerging workload by adaptively retasking vehicles. The SR method is then further extended into a non-myopic setting, where the vehicles can make a decision taking into account how the future goals will change, given the available resource and estimation of expected workload. Simulation results show that the SR setting provides a way to tackle the high computational complexity load, common for non-myopic solutions. Validation of the SR method is based on trial data and experiments performed using a robotics framework, MOOS-IvP. This thesis develops and evaluates the SR method, a mission planning approach for underwater robotic cooperation in communication and resource constraint environment.
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Goh, Hock Guan. "Cognitive wireless sensor networks (CogWSNs)." Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24216.
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Cognitive Wireless Sensor Networks (CogWSNs) are an adaptive learning based wireless sensor network relying on cognitive computational processes to provide a dynamic capability in configuring the network. The network is formed by sensor nodes equipped with cognitive modules with awareness of their operating environment. If the performance of the sensor network does not meet requirements during operation, a corrective action is derived from stored network knowledge to improve performance. After the action is implemented, feedback on the action taken is evaluated to determine the level of improvement. Example functions within CogWSNs can be as simple as to provide robust connectivity or as complex as to negotiate additional resources from neighbouring network groups with the goal of forwarding application-critical data. In this work, the concept of CogWSNs is defined and its decision processes and supporting architecture proposed. The decision role combines the Problem Solving cognitive process from A Layered Reference Model of the Brain and Polya Concept, consisting of Observe, Plan, Implement, and Evaluate phases. The architecture comprises a Transceiver, Transducer, and Power Supply virtual modules coordinated by the CogWSN's decision process together with intervention, if necessary, by a user. Three types of CogWSN modules are designed based on different implementation considerations: Rule-based CogWSN, Supervised CogWSN, and Reinforcement CogWSN. Verification and comparison for these modules are executed through case studies with focus on power transmission and communication slot allocation. Results show that all three modules are able to achieve targeted connectivity and maintain utilisation of slots at acceptable data rates.
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Wen, Hongkai. "Accuracy estimation for sensor networks." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:4ce383e9-7223-48bc-a461-83e19b1afe64.
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With sensor technology gaining maturity and becoming ubiquitous, we are experiencing an unprecedented wealth of sensor data. In most sensing scenarios, the measurements generated by sensor networks are noisy and usually annotated with some measure of uncertainty. The problem we address in this thesis is how to estimate the accuracy of the sensor systems based on the probabilistic measurements they provide. This problem is increasingly common in many settings, such as multiple sensing services are competing for the same group of users, detecting faults in large scale networks, or establishing trustworthiness of different individuals in social sensing. It is also challenging in many ways, for instance, the ground truth of the monitored states is absent, the users often lack a clear view of the implementation details of the sensor systems, and the reported accuracy can be misleading. To address theses challenges, in this thesis we formulate the problem of estimating the accuracy of sensor systems in a general manner that applies to a broad spectrum of sensing scenarios. We then propose an accuracy estimation framework that breaks the problem into layers, which can be implemented in different ways. We present a novel inference-based accuracy estimation approach, which assesses the accuracy of sensor systems by comparing the reported measurements with the states inferred with the probabilistic measurements from all systems and available prior knowledge. We also propose a new learning-based approach for accuracy estimation, which employs novel parameter learning techniques. The learned parameters are either used to improve estimating the accuracy of sensor measurements, or to derive the accuracy of sensor systems directly in certain cases. We perform a systematic experimental evaluation on two datasets collected from real-world sensor deployments, where an array of different approaches are juxtaposed and compared extensively. We discuss how they trade accuracy for computation cost, and how this trade-off largely depends on the knowledge of the sensing scenarios. We also show that the proposed approaches outperform the competing ones in estimating accuracy and ranking the sensor systems.
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Zhang, Luxin. "Optimal scheduling in sensor networks." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/49219.
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We aim to address, some of the fundamentals on how to model the optimal control of data problems arising in this big data era accurately and effectively. In this thesis, we have introduced a framework for formulating and solving the optimal scheduling problem of both communication and computation in a sensor network, with minimising the latency, i.e. the overall task completion time, and the total energy consumption as the objectives. We are able to schedule both the communication and computation by formulating the proposed optimal scheduling problem as a nonlinear programming (NLP) problem. We present two novel optimal scheduling problems in sensor networks: a single objective scheduling problem, minimising the overall task completion time, and a bi-objective scheduling problem, minimising both the overall task completion time and the total energy consumption. We propose the design of a decentralised discrete processing and transmission protocol, effectively turning the continuous-time, uncountable speed set solution into a discrete-time, countable speed set implementation. This significantly reduces the computation complexity compared to solving a mixed integer nonlinear programming (MINLP) instead. By implementing the normal constraint (NC) method, we are able to generate an evenly-distributed point-wise approximation of the Pareto curve to show the energy and latency trade-offs of our proposed bi-objective optimal scheduling problem. The Pareto curve can provide a guideline and reference for parameter design and selection. We also demonstrate how to modify and implement our framework by studying the optimal communication setup of smart meters in a smart building. The modified formulation and several case studies on optimal communication topology and transmission rates setups in various smart meter networks are presented. Numerical results show that the overall energy consumption can be reduced by implementing the optimal communication architecture and transmission rate setup, rather than implementing a straightforward communication architecture with uniform channel bandwidth.
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Krol, Michal. "Routin in wireless sensor networks." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAM004/document.
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Le paradigme d’Internet des objets (IoT) envisage d’élargir Internet actuelle avec un grand nombre de dispositifs intelligents. Réseaux de Capteurs sans Fil (WSN) déploie les dispositifs fonctionnant sur des approvisionnements énergétiques maigres et mesurant de phénomènes environnementaux (comme la température, la radioactivité, ou CO 2). Des applications populaires de WSN comprennent la surveillance, le télémétrie, et la prévention des catastrophes naturelles. Des défis majeurs de WSN sont comment permettre à l’efficacité énergétique, surmonter les déficiences de support sans fil, et d’opérer dans à la manière auto-organisée. L’intégration de WSN dans IoT se posera sur des standards ouvertes efforçant d’offrir évolutivité et de fiabilité dans une variété de scénarios et conditions de fonctionnement. Néanmoins, l’état actuel des standards a les problèmes d’interopérabilité et peuvent bénéficier de certaines améliorations. Les contributions de la thèse sont :Nous avons effectué une étude approfondie des filtres de Bloom et de leur utilisation dans le stockage de caractéristiques de nœud dans l’adresse IP. Différentes techniques de compression et de variantes de filtres nous ont permisde développer un système efficace qui comble l’écart entre le routage de caractéristiques et l’approche classique compatible avec les réseaux IPv6.Nous proposons Featurecast, un protocole de routage / service de nommage pourWSN. Il permet d’interroger les réseaux de capteurs en utilisant un ensemble de caractéristiques tout raccord en entête de paquet IPv6. Nous intégrons notre protocole dans RPL et introduisons une nouvelle mesure, qui augmentent l’efficacité de routage. Nous vérifions sa performance contre dans des simulations approfondies et des test sur des capteurs réels dans un bancd’essai à grande échelle. Simulations approfondies démontrent les avantagesde notre protocole en termes d’utilisation de la mémoire, le surcharge de con-trôle, le taux de livraison de paquets et la consommation d’énergie.Nous introduisons WEAVE - un protocole de routage pour les réseaux avec géolo-calisation. Notre solution n’utilise pas de message de contrôle et apprend sesvoies seulement en observant le trafic. Plusieurs mécanismes sont introduitspour garder un en-tête de taille fixe, contourner à la fois les petits commeles grands obstacles et fournir une communication efficace entre les nœuds.Nous avons effectué des simulations à grande échelle impliquant plus de 19000noeuds et des expériences avec des capteurs réels sur banc d’essai IoT-lab.Nos résultats montrent que nous atteignons bien meilleures performances enparticulier dans les réseaux grands et dynamiques sans introduire de surchargeInternet of Things (IoT) paradigm envisages to expand the current Internet witha huge number of intelligent communicating devices. Wireless Sensor Networks(WSN) deploy the devices running on meagre energy supplies and measuring environmental phenomena (like temperature, radioactivity, or CO 2 ). WSN popularapplications include monitoring, telemetry, and natural disaster prevention. Major WSN challenges are energy efficiency, overcome impairments of wireless medium, and operate in the self-organisation. The WSN integrating IoT will rely on a set of the open standards striving to offer scalability and reliability in a variety of the operating scenarios and conditions. Nevertheless, the current state of the standards have interoperability issues and can benefit from further improvements. The contributions of the thesis work are:We performed an extensive study of Bloom Filters and their use in storing nodetext-based elements in IP address. Different techniques of compression andvariants of filters allowed us to develop an efficient system closing the gapbetween feature-routing and classic approach compatible with IPv6 networks.We propose Featurecast, a routing protocol/naming service for WSN. It allowsto query sensor networks using a set of characteristics while fitting in anIPv6 packet header. We integrate our protocol in RPL and introduce a newmetric, which increase the routing efficiency. We check its performance inboth extensive simulations and experimentations on real sensors in a large-scale Senslab testbed. Large-scale simulations demonstrate the advantagesof our protocol in terms of memory usage, control overhead, packet deliveryrate and energy consumption.We introduce WEAVE - a routing protocol for networks with geolocation. Our so-lution does not use any control message and learn its paths only by observingthe traffic. Several mechanisms are introduce to keep a fixed-size header andbypass both small as well as large obstacles and provide an efficient communication between nodes. We performed simulations on large scale involvingmore than 19000 nodes and real-sensor experimentations on IoT-lab testbed. Our results show that we achieve much better performance especially in large and dynamic networks without introducing any control overhead
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Rezgui, Abdelmounaam. "Service-Oriented Sensor-Actuator Networks." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/30098.
Full textAbstract:
In this dissertation, we propose service-oriented sensor-actuator networks (SOSANETs) as a new paradigm for building the next generation of customizable, open, interoperable sensor-actuator networks. In SOSANETs, nodes expose their capabilities to applications in the form of service profiles. A node's service profile consists of a set of services (i.e., sensing and actuation capabilities) that it provides and the quality of service (QoS) parameters associated with those services (delay, accuracy, freshness, etc.). SOSANETs provide the benefits of both application-specific SANETs and generic SANETs. We first define a query model and an architecture for SOSANETs. The proposed query model offers a simple, uniform query interface whereby applications specify sensing and actuation queries independently from any specific deployment of the underlying SOSANET. We then present uRACER (Reliable Adaptive serviCe-driven Efficient Routing), a routing protocol suite for SOSANETs. uRACER consists of three routing protocols,
namely, SARP (Service-Aware Routing Protocol), CARP (Context-Aware Routing Protocol), and TARP (Trust-Aware Routing Protocol). SARP uses an efficient service-aware routing approach that aggressively reduces downstream traffic by translating service profiles into efficient paths. CARP supports QoS by dynamically adapting each node's routing behavior and service profile according to the current context of that node, i.e. number of pending queries and number and type of messages to be routed. Finally, TARP achieves high end-to-end reliability through a scalable reputation-based approach in which each node is able to locally estimate the next hop of the most reliable path to the sink. We also propose query optimization techniques that contribute to the efficient execution of queries in SOSANETs. To evaluate the proposed service-oriented architecture, we implemented TinySOA, a prototype SOSANET built on top of TinyOS with uRACER as its routing mechansim. TinySOA is designed as a set of layers with a loose interaction model that enables several cross-layer optimization options. We conducted an evaluation of TinySOA that included a comparison with TinyDB. The obtained empirical results show that TinySOA achieves significant improvements on many aspects including energy consumption, scalability, reliability and response time.Ph. D.