Modeling Security and Cooperation in Wireless Networks Using Game Theory

This research involves the design, development, and theoretical demonstration of models resulting in integrated misbehavior resolution protocols for ad hoc networked devices. Game theory was used to analyze strategic interaction among independent devices with conflicting interests. Packet forwarding at the routing layer of autonomous ad hoc networks was investigated. Unlike existing reputation based or payment schemes, this model is based on repeated interactions. To enforce cooperation, a community enforcement mechanism was used, whereby selfish nodes that drop packets were punished not only by the victim, but also by all nodes in the network. Then, a stochastic packet forwarding game strategy was introduced. Our solution relaxed the uniform traffic demand that was pervasive in other works. To address the concerns of imperfect private monitoring in resource aware ad hoc networks, a belief-free equilibrium scheme was developed that reduces the impact of noise in cooperation. This scheme also eliminated the need to infer the private history of other nodes. Moreover, it simplified the computation of an optimal strategy. The belief-free approach reduced the node overhead and was easily tractable. Hence it made the system operation feasible. Motivated by the versatile nature of evolutionary game theory, the assumption of a rational node is relaxed, leading to the development of a framework for mitigating routing selfishness and misbehavior in Multi hop networks. This is accomplished by setting nodes to play a fixed strategy rather than independently choosing a rational strategy. A range of simulations was carried out that showed improved cooperation between selfish nodes when compared to older results. Cooperation among ad hoc nodes can also protect a network from malicious attacks. In the absence of a central trusted entity, many security mechanisms and privacy protections require cooperation among ad hoc nodes to protect a network from malicious attacks. Therefore, using game theory and evolutionary game theory, a mathematical framework has been developed that explores trust mechanisms to achieve security in the network. This framework is one of the first steps towards the synthesis of an integrated solution that demonstrates that security solely depends on the initial trust level that nodes have for each other

A Scalable Trust Management scheme for Mobile Ad Hoc Networks

Mobile ad hoc networks MANETs, have special resource requirements and different topology features, they establish themselves on fly without reliance on centralized or specialized entities such as base stations. All the nodes must cooperate with each other in order to send packets, forwarding packets, responding to routing messages, sending recommendations, among others, Cooperating nodes must trust each other. In MANETs, an untrustworthy node can wreak considerable damage and adversely affect the quality and reliability of data. Therefore, analyzing the trust level of a node has a positive influence on the confidence with which an entity conducts transactions with that node. This thesis presents a new trust management scheme to assign trust levels for spaces or nodes in ad hoc networks. The scheme emulates the human model which depends on the previous individual experience and on the intercession or recommendation of other spaces in the same radio range. The trust level considers the recommendation of trustworthy neighbors and their own experience. For the recommendation computation, we take into account not only the trust level, but also its accuracy and the relationship maturity. The relationship rationality -maturity-, allows nodes to improve the efficiency of the proposed model for mobile scenarios. We also introduce the Contribution Exchange Protocol (CEP) which allows nodes to exchange Intercessions and recommendation about their neighbors without disseminating the trust information over the entire network. Instead, nodes only need to keep and exchange trust information about nodes within the radio range. Without the need for a global trust knowledge. Different from most related works, this scheme improves scalability by restricting nodes to keep and exchange trust information solely with direct neighbors, that is, neighbors within the radio range. We have developed a simulator, which is specifically designed for this model, in order to evaluate and identify the main characteristics of the proposed system. Simulation results show the correctness of this model in a single-hop network. Extending the analysis to mobile multihop networks, shows the benefits of the maturity relationship concept, i.e. for how long nodes know each other, the maturity parameter can decrease the trust level error up to 50%. The results show the effectiveness of the system and the influence of main parameters in the presence of mobility. At last, we analyze the performance of the CEP protocol and show its scalability. We show that this implementation of CEP can significantly reduce the number messages

Energy Efficient and Secure Wireless Sensor Networks Design

Wireless Sensor Networks (WSNs) are emerging technologies that have the ability to sense, process, communicate, and transmit information to a destination, and they are expected to have significant impact on the efficiency of many applications in various fields. The resource constraint such as limited battery power, is the greatest challenge in WSNs design as it affects the lifetime and performance of the network. An energy efficient, secure, and trustworthy system is vital when a WSN involves highly sensitive information. Thus, it is critical to design mechanisms that are energy efficient and secure while at the same time maintaining the desired level of quality of service. Inspired by these challenges, this dissertation is dedicated to exploiting optimization and game theoretic approaches/solutions to handle several important issues in WSN communication, including energy efficiency, latency, congestion, dynamic traffic load, and security. We present several novel mechanisms to improve the security and energy efficiency of WSNs. Two new schemes are proposed for the network layer stack to achieve the following: (a) to enhance energy efficiency through optimized sleep intervals, that also considers the underlying dynamic traffic load and (b) to develop the routing protocol in order to handle wasted energy, congestion, and clustering. We also propose efficient routing and energy-efficient clustering algorithms based on optimization and game theory. Furthermore, we propose a dynamic game theoretic framework (i.e., hyper defense) to analyze the interactions between attacker and defender as a non-cooperative security game that considers the resource limitation. All the proposed schemes are validated by extensive experimental analyses, obtained by running simulations depicting various situations in WSNs in order to represent real-world scenarios as realistically as possible. The results show that the proposed schemes achieve high performance in different terms, such as network lifetime, compared with the state-of-the-art schemes

Smart Wireless Sensor Networks

The recent development of communication and sensor technology results in the growth of a new attractive and challenging area - wireless sensor networks (WSNs). A wireless sensor network which consists of a large number of sensor nodes is deployed in environmental fields to serve various applications. Facilitated with the ability of wireless communication and intelligent computation, these nodes become smart sensors which do not only perceive ambient physical parameters but also be able to process information, cooperate with each other and self-organize into the network. These new features assist the sensor nodes as well as the network to operate more efficiently in terms of both data acquisition and energy consumption. Special purposes of the applications require design and operation of WSNs different from conventional networks such as the internet. The network design must take into account of the objectives of specific applications. The nature of deployed environment must be considered. The limited of sensor nodes� resources such as memory, computational ability, communication bandwidth and energy source are the challenges in network design. A smart wireless sensor network must be able to deal with these constraints as well as to guarantee the connectivity, coverage, reliability and security of network's operation for a maximized lifetime. This book discusses various aspects of designing such smart wireless sensor networks. Main topics includes: design methodologies, network protocols and algorithms, quality of service management, coverage optimization, time synchronization and security techniques for sensor networks

Modelo de confiança para redes AD HOC baseado em teoria de jogos

Orientador: Prof. Dr. Luiz Carlos Pessoa AlbiniCoorientador: Prof. Dr. André L. VignattiDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Exatas, Curso de Pós-Graduação em Informática. Defesa: Curitiba, 31/08/2013Bibliografia: fls. 49-55Resumo: Confiança e tratada como uma explicação para a diferença entre o comportamento humano real e aquele que pode ser explicado pelo desejo individual para maximizar a própria utilidade. Em termos gerais, a confianca e uma atribulo a relacão entre indivíduos ou grupos. Este trabalho propoe um modelo de confianca para Redes Ad Hoc baseado em Teoria de Jogos com o objetivo de responder a seguinte questao: Qual a confiança de um no em outro? O modelo de confiança proposto, chamado TrustUm, calcula o valor de confianca atraves de informacoes trocadas entre os proprios nos e de testes realizados em seus vizinhos. O TrustUm esta dividido em três etapas: monitoramento de vizinhos, troca de informações e calculo de confianca. A troca de informacoes utiliza os conceitos de Teoria de Jogos, utilizando o Jogo do Ultimato, atraves do qual o comportamento dos nos da rede e analisado. Atraves dos resultados obtidos dessa analise e calculado um valor de confiança para cada no da rede. Os resultados demostram que o modelo consegue inicialmente realizar as trocas de mensagens, otimizando o recebimento de informaçcãoes confiáveis. Tambem o resultado aponta um valor de confianca embasado na ancianidade das informacoes trocadas e baseado nas informacoes dos proprios nos. Os resultados apontam uma diminuicão de ate 70% de informacães maliciosas trocadas na rede, alem de um cáalculo de confiancça mais preciso.Abstract: Trust is treated as an explanation for the difference between real and human behavior which can be explained by the desire to maximize their own utility. In general, trust is an assignment to the relationship between individuals or groups. This project proposes a trust model for ad hoc networks based on game theory. The proposal aims to answer the following question: How much a given node trusts another given node? The proposed trust model, called TrustUm calculates the trust value through information exchanged with the nodes themselves and with tests of its neighbors. To this end, some mathematical models were used to guide the calculation, and also by parameters set by the application that will use this model. The TrustUm is divided into three steps: monitoring neighbors, exchange of information and calculation of trust. The exchange of information uses the concepts of Game Theory, using the Ultimatum Game, where the behavior of the network nodes will be analyzed and the results obtained through this analysis will be calculated a trust value to each network node. The results show that the model can first select the message exchanges, optimizing the receipt of reliable information. Furthermore, the result indicates a trust value based on old information and based on information from the nodes. The results show a decrease of 30% to 70% of malicious information exchanged in the network, and a more precise trust value