Systematic Design of Trust Management Systems for Wireless Sensor Networks: A Review
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paper_title: A Novel Heuristic Approach Based Trust Worthy Architecture for Wireless Sensor Networks

paper_content:

A Wireless Sensor Networks (WSNs) consist of spatially distributed autonomous sensors to cooperatively monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, motion or pollutants. WSNs are more vulnerable to attacks and failures due to the involvement of many numbers of tiny sensor nodes. As the technology is tremendously increasing in the recent past, the implementation of this for various time critical applications is quite interesting and challenging. Moreover, WSNs have no specific hierarchical structures, leads to security and maintenance problems. Trust in WSN is defined as the degree of belief or confidence about the nodes based on the past interactions and observations has which become a mandatory requirement for reliable communication in WSN under security constraints. In this paper, we propose a Heuristic Approach based Trust Worthy Architecture for WSN that considers the challenges of the system and focus on the collaborative mechanism for trust evaluation and maintenance. Our proposed Architecture could also be capable of fulfilling critical security, reliability, mobility and performance requirements for reliable communication while being readily adaptable to different applications. The simulation results of the proposed architecture outperformed the recent trust worthy architecture using the analysis of the performance requirements such as communication overhead, memory requirements and energy consumption.
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paper_title: Design and Implementation of TARF: A Trust-Aware Routing Framework for WSNs

paper_content:

The multihop routing in wireless sensor networks (WSNs) offers little protection against identity deception through replaying routing information. An adversary can exploit this defect to launch various harmful or even devastating attacks against the routing protocols, including sinkhole attacks, wormhole attacks, and Sybil attacks. The situation is further aggravated by mobile and harsh network conditions. Traditional cryptographic techniques or efforts at developing trust-aware routing protocols do not effectively address this severe problem. To secure the WSNs against adversaries misdirecting the multihop routing, we have designed and implemented TARF, a robust trust-aware routing framework for dynamic WSNs. Without tight time synchronization or known geographic information, TARF provides trustworthy and energy-efficient route. Most importantly, TARF proves effective against those harmful attacks developed out of identity deception; the resilience of TARF is verified through extensive evaluation with both simulation and empirical experiments on large-scale WSNs under various scenarios including mobile and RF-shielding network conditions. Further, we have implemented a low-overhead TARF module in TinyOS; as demonstrated, this implementation can be incorporated into existing routing protocols with the least effort. Based on TARF, we also demonstrated a proof-of-concept mobile target detection application that functions well against an antidetection mechanism.
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paper_title: Trust mechanisms in wireless sensor networks: Attack analysis and countermeasures

paper_content:

As the trust issue in wireless sensor networks is emerging as one important factor in security schemes, it is necessary to analyze how to resist attacks with a trust scheme. In this paper we categorize various types of attacks and countermeasures related to trust schemes in WSNs. Furthermore, we provide the development of trust mechanisms, give a short summarization of classical trust methodologies and emphasize the challenges of trust scheme in WSNs. An extensive literature survey is presented by summarizing state-of-the-art trust mechanisms in two categories: secure routing and secure data. Based on the analysis of attacks and the existing research, an open field and future direction with trust mechanisms in WSNs is provided.
---
paper_title: A Novel Trust-Aware Geographical Routing Scheme for Wireless Sensor Networks

paper_content:

Wireless sensor networks are vulnerable to a wide set of security attacks, including those targeting the routing protocol functionality. The applicability of legacy security solutions is disputable (if not infeasible), due to severe restrictions in node and network resources. Although confidentiality, integrity and authentication measures assist in preventing specific types of attacks, they come at high cost and, in most cases, cannot shield against routing attacks. To face this problem, we propose a secure routing protocol which adopts the geographical routing principle to cope with the network dimensions, and relies on a distributed trust model for the detection and avoidance of malicious neighbours. A novel function which adaptively weights location, trust and energy information drives the routing decisions, allowing for shifting emphasis from security to path optimality. The proposed trust model relies on both direct and indirect observations to derive the trustworthiness of each neighboring node, while it is capable of defending against an increased set of routing attacks including attacks targeting the indirect trust management scheme. Extensive simulation results reveal the advantages of the proposed model.
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paper_title: Trust Computations and Trust Dynamics in Mobile Adhoc Networks: A Survey

paper_content:

Trust is an important aspect of mobile adhoc networks (MANETs). It enables entities to cope with uncertainty and uncontrollability caused by the free will of others. Trust computations and management are highly challenging issues in MANETs due to computational complexity constraints, and the independent movement of component nodes. This prevents the direct application of techniques suited for other networks. 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. In this work we present a detailed survey on various trust computing approaches that are geared towards MANETs. We highlight the summary and comparisons of these approaches. In addition, we analyze various works on trust dynamics including trust propagation, prediction and aggregation algorithms, the influence of network dynamics on trust dynamics and the impact of trust on security services.
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paper_title: Hierarchical Trust Management for Wireless Sensor Networks and its Applications to Trust-Based Routing and Intrusion Detection

paper_content:

We propose a highly scalable cluster-based hierarchical trust management protocol for wireless sensor networks (WSNs) to effectively deal with selfish or malicious nodes. Unlike prior work, we consider multidimensional trust attributes derived from communication and social networks to evaluate the overall trust of a sensor node. By means of a novel probability model, we describe a heterogeneous WSN comprising a large number of sensor nodes with vastly different social and quality of service (QoS) behaviors with the objective to yield "ground truth" node status. This serves as a basis for validating our protocol design by comparing subjective trust generated as a result of protocol execution at runtime against objective trust obtained from actual node status. To demonstrate the utility of our hierarchical trust management protocol, we apply it to trust-based geographic routing and trust-based intrusion detection. For each application, we identify the best trust composition and formation to maximize application performance. Our results indicate that trust-based geographic routing approaches the ideal performance level achievable by flooding-based routing in message delivery ratio and message delay without incurring substantial message overhead. For trust-based intrusion detection, we discover that there exists an optimal trust threshold for minimizing false positives and false negatives. Furthermore, trust-based intrusion detection outperforms traditional anomaly-based intrusion detection approaches in both the detection probability and the false positive probability.
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paper_title: Wireless sensor networks: a survey

paper_content:

This paper describes the concept of sensor networks which has been made viable by the convergence of micro-electro-mechanical systems technology, wireless communications and digital electronics. First, the sensing tasks and the potential sensor networks applications are explored, and a review of factors influencing the design of sensor networks is provided. Then, the communication architecture for sensor networks is outlined, and the algorithms and protocols developed for each layer in the literature are explored. Open research issues for the realization of sensor networks are also discussed.
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paper_title: ZoneTrust: Fast Zone-Based Node Compromise Detection and Revocation in Wireless Sensor Networks Using Sequential Hypothesis Testing

paper_content:

Due to the unattended nature of wireless sensor networks, an adversary can physically capture and compromise sensor nodes and then mount a variety of attacks with the compromised nodes. To minimize the damage incurred by the compromised nodes, the system should detect and revoke them as soon as possible. To meet this need, researchers have recently proposed a variety of node compromise detection schemes in wireless ad hoc and sensor networks. For example, reputation-based trust management schemes identify malicious nodes but do not revoke them due to the risk of false positives. Similarly, software-attestation schemes detect the subverted software modules of compromised nodes. However, they require each sensor node to be attested periodically, thus incurring substantial overhead. To mitigate the limitations of the existing schemes, we propose a zone-based node compromise detection and revocation scheme in wireless sensor networks. The main idea behind our scheme is to use sequential hypothesis testing to detect suspect regions in which compromised nodes are likely placed. In these suspect regions, the network operator performs software attestation against sensor nodes, leading to the detection and revocation of the compromised nodes. Through quantitative analysis and simulation experiments, we show that the proposed scheme detects the compromised nodes with a small number of samples while reducing false positive and negative rates, even if a substantial fraction of the nodes in the zone are compromised. Additionally, we model the detection problem using a game theoretic analysis, derive the optimal strategies for the attacker and the defender, and show that the attacker's gain from node compromise is greatly limited by the defender when both the attacker and the defender follow their optimal strategies.
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paper_title: A Trust-Based Framework for Fault-Tolerant Data Aggregation in Wireless Multimedia Sensor Networks

paper_content:

For wireless multimedia sensor networks (WMSNs) deployed in noisy and unattended environments, it is necessary to establish a comprehensive framework that protects the accuracy of the gathered multimedia information. In this paper, we jointly consider data aggregation, information trust, and fault tolerance to enhance the correctness and trustworthiness of collected information. Based on the multilayer aggregation architecture of WMSNs, we design a trust-based framework for data aggregation with fault tolerance with a goal to reduce the impact of erroneous data and provide measurable trustworthiness for aggregated results. By extracting statistical characteristics from different sources and extending Josang's trust model, we propose how to compute self-data trust opinion, peer node trust opinion, and peer data trust opinion. According to the trust transfer and trust combination rules designed in our framework, we derive the trust opinion of the sink node on the final aggregated result. In particular, this framework can evaluate both discrete data and continuous media streams in WMSNs through a uniform mechanism. Results obtained from both simulation study and experiments on a real WMSN testbed demonstrate the validity and efficiency of our framework, which can significantly improve the quality of multimedia information as well as more precisely evaluate the trustworthiness of collected information.
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paper_title: An Iterative Algorithm for Trust Management and Adversary Detection for Delay-Tolerant Networks

paper_content:

Delay/Disruption Tolerant Networks (DTNs) have been identified as one of the key areas in the field of wireless communication, wherein sparseness and delay are particularly high. They are emerging as a promising technology in vehicular, planetary/interplanetary, military/tactical, disaster response, underwater and satellite networks. DTNs are characterized by large end-to-end communication latency and the lack of end-to-end path from a source to its destination. These characteristics pose several challenges to the security of DTNs. Especially, Byzantine attacks in which one or more legitimate nodes have been compromised and fully controlled by the adversary can give serious damages to the network in terms of latency and data availability. Using reputation-based trust management systems is shown to be an effective way to handle the adversarial behavior in Mobile Ad hoc Networks (MANETs). However, because of the unique characteristics of DTNs, those traditional techniques do not apply to DTNs. Our main objective in this paper is to develop a robust trust mechanism and an efficient and low cost malicious node detection technique for DTNs. Inspired by our recent results on reputation management for online systems and e-commerce, we develop an iterative malicious node detection mechanism for DTNs referred as ITRM. The proposed scheme is a graph-based iterative algorithm motivated by the prior success of message passing techniques for decoding low-density parity-check codes over bipartite graphs. Applying ITRM to DTNs for various mobility models, we observed that the proposed iterative reputation management scheme is far more effective than well-known reputation management techniques such as the Bayesian framework and EigenTrust. Further, we concluded that the proposed scheme provides high data availability and packet-delivery ratio with low latency in DTNs under various adversary attacks which attempt to both undermine the trust and detection scheme and the packet delivery protocol.
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paper_title: Are you contributing trustworthy data?: the case for a reputation system in participatory sensing

paper_content:

Participatory sensing is a revolutionary new paradigm in which volunteers collect and share information from their local environment using mobile phones. The inherent openness of this platform makes it easy to contribute corrupted data. This paper proposes a novel reputation system that employs the Gompertz function for computing device reputation score as a reflection of the trustworthiness of the contributed data. We implement this system in the context of a participatory noise monitoring application and conduct extensive real-world experiments using Apple iPhones. Experimental results demonstrate that our scheme achieves three-fold improvement in comparison with the state-of-the-art Beta reputation scheme.
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paper_title: A quantitative trust establishment framework for reliable data packet delivery in MANETs

paper_content:

In mobile ad hoc networks (MANETs), a source node must rely on other nodes to forward its packets on multi-hop routes to the destination. Secure and reliable handling of packets by the intermediate nodes is difficult to ensure in an ad hoc environment. We propose a trust establishment scheme for MANETs which aims to improve the reliability of packet forwarding over multi-hop routes in the presence of potentially malicious nodes. Each node forms an "opinion" about each of the other nodes based on both first and second-hand observation data collected from the network. The opinion metric can be incorporated into ad hoc routing protocols to achieve reliable packet delivery even when a portion of the network exhibits malicious behavior. We present numerical results which demonstrate the effectiveness of the proposed trust establishment scheme.
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paper_title: Statistical trust establishment in wireless sensor networks

paper_content:

We present a new distributed approach that establishes reputation-based trust among sensor nodes in order to identify malfunctioning and malicious sensor nodes and minimize their impact on applications. Our method adapts well to the special characteristics of wireless sensor networks, the most important being their resource limitations. Our methodology computes statistical trust and a confidence interval around the trust based on direct and indirect experiences of sensor node behavior. By considering the trust confidence interval, we are able to study the tradeoff between the tightness of the trust confidence interval with the resources used in collecting experiences. Furthermore, our approach allows dynamic scaling of redundancy levels based on the trust relationship between the nodes of a wireless sensor network. Using extensive simulations we demonstrate the benefits of our approach over an approach that uses static redundancy levels in terms of reduced energy consumption and longer life of the network. We also find that high confidence trust can be computed on each node with a relatively small memory overhead and used to determine the level of redundancy operations among nodes in the system.
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paper_title: Mitigating routing misbehavior in mobile ad hoc networks

paper_content:

This paper describes two techniques that improve throughput in an ad hoc network in the presence of nodes that agree to forward packets but fail to do so. To mitigate this problem, we propose categorizing nodes based upon their dynamically measured behavior. We use a watchdog that identifies misbehaving nodes and a pathrater that helps routing protocols avoid these nodes. Through simulation we evaluate watchdog and pathrater using packet throughput, percentage of overhead (routing) transmissions, and the accuracy of misbehaving node detection. When used together in a network with moderate mobility, the two techniques increase throughput by 17% in the presence of 40% misbehaving nodes, while increasing the percentage of overhead transmissions from the standard routing protocol's 9% to 17%. During extreme mobility, watchdog and pathrater can increase network throughput by 27%, while increasing the overhead transmissions from the standard routing protocol's 12% to 24%.
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paper_title: Tampering with Motes: Real-World Physical Attacks on Wireless Sensor Networks

paper_content:

Most security protocols for wireless sensor networks (WSN) assume that the adversary can gain full control over a sensor node through direct physical access (node capture attack). But so far the amount of effort an attacker has to undertake in a node capture attack is unknown. In our project we evaluate different physical attacks against sensor node hardware. Detailed knowledge about the effort needed for physical attacks allows to fine tune security protocols in WSNs so they provide optimal protection at minimal cost.
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paper_title: Denial of Service in Sensor Networks

paper_content:

Sensor networks hold the promise of facilitating large-scale, real-time data processing in complex environments, helping to protect and monitor military, environmental, safety-critical, or domestic infrastructures and resources, Denial-of-service attacks against such networks, however, may permit real world damage to public health and safety. Without proper security mechanisms, networks will be confined to limited, controlled environments, negating much of the promise they hold. The limited ability of individual sensor nodes to thwart failure or attack makes ensuring network availability more difficult. To identify denial-of-service vulnerabilities, the authors analyzed two effective sensor network protocols that did not initially consider security. These examples demonstrate that consideration of security at design time is the best way to ensure successful network deployment.
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paper_title: Trust mechanisms in wireless sensor networks: Attack analysis and countermeasures

paper_content:

As the trust issue in wireless sensor networks is emerging as one important factor in security schemes, it is necessary to analyze how to resist attacks with a trust scheme. In this paper we categorize various types of attacks and countermeasures related to trust schemes in WSNs. Furthermore, we provide the development of trust mechanisms, give a short summarization of classical trust methodologies and emphasize the challenges of trust scheme in WSNs. An extensive literature survey is presented by summarizing state-of-the-art trust mechanisms in two categories: secure routing and secure data. Based on the analysis of attacks and the existing research, an open field and future direction with trust mechanisms in WSNs is provided.
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paper_title: Engineering human trust in mobile system collaborations

paper_content:

Rapid advances in wireless networking technologies have enabled mobile devices to be connected anywhere and anytime. While roaming, applications on these devices dynamically discover hosts and services with whom interactions can be started. However, the fear of exposure to risky transactions with potentially unknown entities may seriously hinder collaboration. To minimise this risk, an engineering approach to the development of trust-based collaborations is necessary. This paper introduces hTrust, a human trust management model and framework that facilitates the construction of trust-aware mobile systems and applications. In particular, hTrust supports: reasoning about trust (trust formation), dissemination of trust information in the network (trust dissemination), and derivation of new trust relationships from previously formed ones (trust evolution). The framework views each mobile host as a self-contained unit, carrying along a portfolio of credentials that are used to prove its trustworthiness to other hosts in an ad-hoc mobile environment. Customising functions are defined to capture the natural disposition to trust of the user of the device inside our trust management framework.
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paper_title: Trust Computations and Trust Dynamics in Mobile Adhoc Networks: A Survey

paper_content:

Trust is an important aspect of mobile adhoc networks (MANETs). It enables entities to cope with uncertainty and uncontrollability caused by the free will of others. Trust computations and management are highly challenging issues in MANETs due to computational complexity constraints, and the independent movement of component nodes. This prevents the direct application of techniques suited for other networks. 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. In this work we present a detailed survey on various trust computing approaches that are geared towards MANETs. We highlight the summary and comparisons of these approaches. In addition, we analyze various works on trust dynamics including trust propagation, prediction and aggregation algorithms, the influence of network dynamics on trust dynamics and the impact of trust on security services.
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paper_title: Establishing Trust In Pure Ad-hoc Networks

paper_content:

An ad-hoc network of wireless nodes is a temporarily formed network, created, operated and managed by the nodes themselves. It is also often termed an infrastructure-less, self-organized, or spontaneous network. Nodes assist each other by passing data and control packets from one node to another, often beyond the wireless range of the original sender. The execution and survival of an ad-hoc network is solely dependent upon the cooperative and trusting nature of its nodes.However, this naive dependency on intermediate nodes makes the ad-hoc network vulnerable to passive and active attacks by malicious nodes. A number of protocols have been developed to secure ad-hoc networks using cryptographic schemes, but all rely on the presence of an omnipresent, and often omniscient, trust authority. As this paper describes, dependence on a central trust authority is an impractical requirement for ad-hoc networks. We present a model for trust-based communication in ad-hoc networks that also demonstrates that a central trust authority is a superfluous requirement. The model introduces the notion of belief and provides a dynamic measure of reliability and trustworthiness in an ad hoc network.
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paper_title: A Trust-Based Geographical Routing Scheme in Sensor Networks

paper_content:

Devices in a sensor network need to work in a hostile environment and they are usually powered by batteries. Yet the whole purpose of deploying a sensor network is to perform distributed collaborative computing, possibly in a massive scale. In a hostile computing environment, the sensor devices might be routinely tampered with. Together with the possibility of faulty devices due to extreme conditions or low power, the trustworthiness of a device varies. Specifically, a device should only communicate with another device which has a trust level above a certain threshold. However, setting up trusted communication channels among sensor devices remains a major challenge. In this paper, we propose a trust-based routing scheme in sensor networks for providing a high level of robustness in node selection based on packet trust requirement with lifetime consideration. Our protocol allows messages to be routed through malicious and faulty devices with the selection of trusted neighbors. On the other hand, the network lifetime can also be prolonged by selecting those with their sensing functions covered by some existing nodes. Simulation results show that our scheme is possible to prolong the lifetime of sensor networks and maintain certain satisfactory delivery ratio.
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paper_title: A quantitative trust establishment framework for reliable data packet delivery in MANETs

paper_content:

In mobile ad hoc networks (MANETs), a source node must rely on other nodes to forward its packets on multi-hop routes to the destination. Secure and reliable handling of packets by the intermediate nodes is difficult to ensure in an ad hoc environment. We propose a trust establishment scheme for MANETs which aims to improve the reliability of packet forwarding over multi-hop routes in the presence of potentially malicious nodes. Each node forms an "opinion" about each of the other nodes based on both first and second-hand observation data collected from the network. The opinion metric can be incorporated into ad hoc routing protocols to achieve reliable packet delivery even when a portion of the network exhibits malicious behavior. We present numerical results which demonstrate the effectiveness of the proposed trust establishment scheme.
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paper_title: The Beta Reputation System

paper_content:

Reputation systems can be used to foster good behaviour and to encourage adherence to contracts in e-commerce. Several reputation systems have been deployed in practical applications or proposed in the literature. This paper describes a new system called the beta reputation system which is based on using beta probability density functions to combine feedback and derive reputation ratings. The advantage of the beta reputation system is flexibility and simplicity as well as its foundation on the theory of statistics.
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paper_title: A Novel Approach to Trust Management in Unattended Wireless Sensor Networks

paper_content:

Unattended Wireless Sensor Networks (UWSNs) are characterized by long periods of disconnected operation and fixed or irregular intervals between sink visits. The absence of an online trusted third party implies that existing WSN trust management schemes are not applicable to UWSNs. In this paper, we propose a trust management scheme for UWSNs to provide efficient and robust trust data storage and trust generation. For trust data storage, we employ a geographic hash table to identify storage nodes and to significantly decrease storage cost. We use subjective logic based consensus techniques to mitigate trust fluctuations caused by environmental factors. We exploit a set of trust similarity functions to detect trust outliers and to sustain trust pollution attacks. We demonstrate, through extensive analyses and simulations, that the proposed scheme is efficient, robust and scalable.
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paper_title: A Trust-Based Framework for Fault-Tolerant Data Aggregation in Wireless Multimedia Sensor Networks

paper_content:

For wireless multimedia sensor networks (WMSNs) deployed in noisy and unattended environments, it is necessary to establish a comprehensive framework that protects the accuracy of the gathered multimedia information. In this paper, we jointly consider data aggregation, information trust, and fault tolerance to enhance the correctness and trustworthiness of collected information. Based on the multilayer aggregation architecture of WMSNs, we design a trust-based framework for data aggregation with fault tolerance with a goal to reduce the impact of erroneous data and provide measurable trustworthiness for aggregated results. By extracting statistical characteristics from different sources and extending Josang's trust model, we propose how to compute self-data trust opinion, peer node trust opinion, and peer data trust opinion. According to the trust transfer and trust combination rules designed in our framework, we derive the trust opinion of the sink node on the final aggregated result. In particular, this framework can evaluate both discrete data and continuous media streams in WMSNs through a uniform mechanism. Results obtained from both simulation study and experiments on a real WMSN testbed demonstrate the validity and efficiency of our framework, which can significantly improve the quality of multimedia information as well as more precisely evaluate the trustworthiness of collected information.
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paper_title: Trust management model for mobile ad hoc network based on analytic hierarchy process and fuzzy theory

paper_content:

Owing to the openness in network topology and the absence of centralised administration in management, mobile ad hoc network (MANET) is vulnerable to attacks from malicious nodes. In order to decrease the hazards from these malicious nodes, the authors incorporate the concept of trust into the MANET, and build a trust management model which is divided into two parts: subjective trust evaluation model and trusted routing model. In subjective trust evaluation model, the credibility of nodes can be evaluated using analytic hierarchy process theory and fuzzy logic rules prediction method. Based on the fuzzy dynamic programming theory, in trusted routing model, the authors present a novel trusted routing algorithm which can kick out the untrustworthy nodes in order to obtain a reliable passage delivery route. As an application of the proposed trusted routing algorithm, a novel reactive routing protocol on the basis of the standard dynamic source routing protocol, called fuzzy trusted dynamic source routing (FTDSR) protocol is proposed. Several experiments have been conducted to evaluate the efficiency of the protocol in malicious node identification and attack resistance. The experimental results show that FTDSR can effectively detect the malicious nodes that guarantee the packet delivery ratio and the network throughput.
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paper_title: ZoneTrust: Fast Zone-Based Node Compromise Detection and Revocation in Wireless Sensor Networks Using Sequential Hypothesis Testing

paper_content:

Due to the unattended nature of wireless sensor networks, an adversary can physically capture and compromise sensor nodes and then mount a variety of attacks with the compromised nodes. To minimize the damage incurred by the compromised nodes, the system should detect and revoke them as soon as possible. To meet this need, researchers have recently proposed a variety of node compromise detection schemes in wireless ad hoc and sensor networks. For example, reputation-based trust management schemes identify malicious nodes but do not revoke them due to the risk of false positives. Similarly, software-attestation schemes detect the subverted software modules of compromised nodes. However, they require each sensor node to be attested periodically, thus incurring substantial overhead. To mitigate the limitations of the existing schemes, we propose a zone-based node compromise detection and revocation scheme in wireless sensor networks. The main idea behind our scheme is to use sequential hypothesis testing to detect suspect regions in which compromised nodes are likely placed. In these suspect regions, the network operator performs software attestation against sensor nodes, leading to the detection and revocation of the compromised nodes. Through quantitative analysis and simulation experiments, we show that the proposed scheme detects the compromised nodes with a small number of samples while reducing false positive and negative rates, even if a substantial fraction of the nodes in the zone are compromised. Additionally, we model the detection problem using a game theoretic analysis, derive the optimal strategies for the attacker and the defender, and show that the attacker's gain from node compromise is greatly limited by the defender when both the attacker and the defender follow their optimal strategies.
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paper_title: Ant-based adaptive trust evidence distribution in MANET

paper_content:

Due to the lack of infrastructure and vulnerability of wireless links, security in ad hoc networks is considered to be much more difficult than in traditional hierarchical networks. Building the trust relationship between entities is a fundamental problem in ad hoc networks, since the availability of servers, which distribute trust certificates, is not guaranteed. Furthermore, the existence of any trusted server might not be assumed either. Therefore, the commonly used key distribution center (KDC) and certification authority (CA) are not applicable in such highly autonomous environments. We propose a scheme for the distribution of trust certificates, which is completely distributed and adaptive to mobility. Our scheme is based on the swarm intelligence paradigm, which has been used for routing both in wired and wireless networks. Our simulations in ns-2 show that it performs very well in ad hoc environments.
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paper_title: Markov Chain-Based Trust Model for Analyzing Trust Value in Distributed Multicasting Mobile Ad Hoc Networks

paper_content:

The multicast mobile ad-hoc network (multicast MANET) is proposed for a sender sending packets to several receivers through a multicast session. Since members of a multicast group changes frequently, the issue of supporting secure authentication and authorization in multicast MANET becomes more critical than the network provided a fixed central authentication (CA) server. This work thus proposes a two-step secure authentication approach for the multicast MANET. First, a Markov chain trust model is proposed to determine the trust value (TV) for each one-hop neighbors. A nodepsilas trust value is analyzed from its previous trust manner in this group. The proposed trust model is proven as an ergodic continuous-time Markov chain model. Second, a node with the highest TV of a group will be selected as the CA server. For increasing reliability, the node with the second highest TV will be selected as the backup CA server that will take over CA when CA fails. The procedures of the secure authentication for group management are detailed. The security analysis of each procedure is analyzed to guarantee that the proposed approach achieves a secure reliable authentication in multicast MANET. Numerical results indicate that the analytical trust value of each mobile node is very close to that of simulation under various situations. The speed of the convergence of the analytical trust value shows that the analytical results are independent of initial values and the trust classes.
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paper_title: Collection tree protocol

paper_content:

This paper presents and evaluates two principles for wireless routing protocols. The first is datapath validation: data traffic quickly discovers and fixes routing inconsistencies. The second is adaptive beaconing: extending the Trickle algorithm to routing control traffic reduces route repair latency and sends fewer beacons. We evaluate datapath validation and adaptive beaconing in CTP Noe, a sensor network tree collection protocol. We use 12 different testbeds ranging in size from 20--310 nodes, comprising seven platforms, and six different link layers, on both interference-free and interference-prone channels. In all cases, CTP Noe delivers > 90% of packets. Many experiments achieve 99.9%. Compared to standard beaconing, CTP Noe sends 73% fewer beacons while reducing topology repair latency by 99.8%. Finally, when using low-power link layers, CTP Noe has duty cycles of 3% while supporting aggregate loads of 30 packets/minute.
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paper_title: Design and Implementation of TARF: A Trust-Aware Routing Framework for WSNs

paper_content:

The multihop routing in wireless sensor networks (WSNs) offers little protection against identity deception through replaying routing information. An adversary can exploit this defect to launch various harmful or even devastating attacks against the routing protocols, including sinkhole attacks, wormhole attacks, and Sybil attacks. The situation is further aggravated by mobile and harsh network conditions. Traditional cryptographic techniques or efforts at developing trust-aware routing protocols do not effectively address this severe problem. To secure the WSNs against adversaries misdirecting the multihop routing, we have designed and implemented TARF, a robust trust-aware routing framework for dynamic WSNs. Without tight time synchronization or known geographic information, TARF provides trustworthy and energy-efficient route. Most importantly, TARF proves effective against those harmful attacks developed out of identity deception; the resilience of TARF is verified through extensive evaluation with both simulation and empirical experiments on large-scale WSNs under various scenarios including mobile and RF-shielding network conditions. Further, we have implemented a low-overhead TARF module in TinyOS; as demonstrated, this implementation can be incorporated into existing routing protocols with the least effort. Based on TARF, we also demonstrated a proof-of-concept mobile target detection application that functions well against an antidetection mechanism.
---
paper_title: A Novel Trust-Aware Geographical Routing Scheme for Wireless Sensor Networks

paper_content:

Wireless sensor networks are vulnerable to a wide set of security attacks, including those targeting the routing protocol functionality. The applicability of legacy security solutions is disputable (if not infeasible), due to severe restrictions in node and network resources. Although confidentiality, integrity and authentication measures assist in preventing specific types of attacks, they come at high cost and, in most cases, cannot shield against routing attacks. To face this problem, we propose a secure routing protocol which adopts the geographical routing principle to cope with the network dimensions, and relies on a distributed trust model for the detection and avoidance of malicious neighbours. A novel function which adaptively weights location, trust and energy information drives the routing decisions, allowing for shifting emphasis from security to path optimality. The proposed trust model relies on both direct and indirect observations to derive the trustworthiness of each neighboring node, while it is capable of defending against an increased set of routing attacks including attacks targeting the indirect trust management scheme. Extensive simulation results reveal the advantages of the proposed model.
---
paper_title: A Novel Heuristic Approach Based Trust Worthy Architecture for Wireless Sensor Networks

paper_content:

A Wireless Sensor Networks (WSNs) consist of spatially distributed autonomous sensors to cooperatively monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, motion or pollutants. WSNs are more vulnerable to attacks and failures due to the involvement of many numbers of tiny sensor nodes. As the technology is tremendously increasing in the recent past, the implementation of this for various time critical applications is quite interesting and challenging. Moreover, WSNs have no specific hierarchical structures, leads to security and maintenance problems. Trust in WSN is defined as the degree of belief or confidence about the nodes based on the past interactions and observations has which become a mandatory requirement for reliable communication in WSN under security constraints. In this paper, we propose a Heuristic Approach based Trust Worthy Architecture for WSN that considers the challenges of the system and focus on the collaborative mechanism for trust evaluation and maintenance. Our proposed Architecture could also be capable of fulfilling critical security, reliability, mobility and performance requirements for reliable communication while being readily adaptable to different applications. The simulation results of the proposed architecture outperformed the recent trust worthy architecture using the analysis of the performance requirements such as communication overhead, memory requirements and energy consumption.
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paper_title: A framework for trust-based cluster head election in wireless sensor networks

paper_content:

The election of a malicious or compromised node as the cluster head is one of the most significant breaches in cluster-based wireless sensor networks. In light of this, we are introducing a distributed trust-based framework and a mechanism for the election of trustworthy cluster heads. Our proposed mechanism reduces the likelihood of compromised and or malicious nodes from being selected as cluster heads. Our premise is that while individual nodes may still be prone to attack, a significant vulnerability is addressed if we prevent the election of compromised cluster heads. We do not seek a 'cure for all solution' rather we introduce a framework and a mechanism to address a potentially significant security breach. We performed an evaluation of our approach and the power consumption of our model, by simulations. The results indicate clear advantages of our approach in preventing the election of untrustworthy cluster heads.
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paper_title: Trust Management Problem in Distributed Wireless Sensor Networks

paper_content:

Sensor network security solutions that have been proposed so far are mostly built on the assumption of a trusted environment, which is not very realistic so we need trust management before deploying any other security solution. Traditional trust management schemes that have been developed for wired and wireless ad-hoc networks are not suitable for wireless sensor networks because of higher consumption of resources such as memory and power. In this paper, we propose a novel lightweight group based trust management scheme (GTMS) for distributed wireless sensor networks in which the whole group will get a single trust value. Instead of using completely centralized or distributed trust management schemes, GTMS uses hybrid trust management approach that helps in keeping minimum resource utilization at the sensor nodes.
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paper_title: A Secure Routing Protocol for Wireless Ad Hoc Networks

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Ad hoc networks, which do not rely on infrastructure such as access points or base stations, can be deployed rapidly and inexpensively even in situations with geographical or time constraints. Ad hoc networks have attractive applications in both military and disaster situations and also in commercial uses like sensor networks or conferencing. However, the nature of ad hoc networks makes them vulnerable to attacks, especially in the routing protocol. How to protect an ad hoc routing protocol is an important research topic. In this paper, we present an on-demand secure routing protocol for ad hoc networks based on a distributed authentication mechanism. The protocol makes use of recommendation and trust evaluation to establish a trust relationship between network entities and uses feedback to adjust it. The protocol does not need the support of a trusted third party and can discover multiple routes between two nodes.
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paper_title: Functional reputation based reliable data aggregation and transmission for wireless sensor networks

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In wireless sensor networks, compromised sensor nodes aim to distort the integrity of data by sending false data reports, injecting false data during data aggregation, and disrupting transmission of aggregated data. Previously known trust systems rely on general reputation concept to prevent these attacks. However, this paper presents a novel reliable data aggregation and transmission protocol, called RDAT, which is based on the concept of functional reputation. Protocol RDAT improves the reliability of data aggregation and transmission by evaluating each type of sensor node action using a respective functional reputation. In addition, protocol RDAT employs a fault tolerant Reed-Solomon coding scheme based multi path data transmission algorithm to ensure the reliable data transmission to the base station. The simulation results show that protocol RDAT significantly improves the reliability of the data aggregation and transmission in the presence of compromised nodes.
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paper_title: A Trust-Based Framework for Fault-Tolerant Data Aggregation in Wireless Multimedia Sensor Networks

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For wireless multimedia sensor networks (WMSNs) deployed in noisy and unattended environments, it is necessary to establish a comprehensive framework that protects the accuracy of the gathered multimedia information. In this paper, we jointly consider data aggregation, information trust, and fault tolerance to enhance the correctness and trustworthiness of collected information. Based on the multilayer aggregation architecture of WMSNs, we design a trust-based framework for data aggregation with fault tolerance with a goal to reduce the impact of erroneous data and provide measurable trustworthiness for aggregated results. By extracting statistical characteristics from different sources and extending Josang's trust model, we propose how to compute self-data trust opinion, peer node trust opinion, and peer data trust opinion. According to the trust transfer and trust combination rules designed in our framework, we derive the trust opinion of the sink node on the final aggregated result. In particular, this framework can evaluate both discrete data and continuous media streams in WMSNs through a uniform mechanism. Results obtained from both simulation study and experiments on a real WMSN testbed demonstrate the validity and efficiency of our framework, which can significantly improve the quality of multimedia information as well as more precisely evaluate the trustworthiness of collected information.
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paper_title: Malicious node detection in wireless sensor networks using weighted trust evaluation

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Deployed in a hostile environment, individual nodes of a wireless sensor network (WSN) could be easily compromised by the adversary due to the constraints such as limited battery lifetime, memory space and computing capability. It is critical to detect and isolate the compromised nodes in order to avoid being misled by the falsified information injected by the adversary through compromised nodes. However, it is challenging to secure the flat topology networks efficiently because of the poor scalability and high communication overhead. On top of a hierarchical WSN architecture, in this paper we proposed a novel scheme based on weighted-trust evaluation to detect malicious nodes. The hierarchical network can reduce the communication overhead between sensor nodes by utilizing clustered topology. Through intensive simulation, we verified the correctness and efficiency of our detection scheme.
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paper_title: Hierarchical Trust Management for Wireless Sensor Networks and its Applications to Trust-Based Routing and Intrusion Detection

paper_content:

We propose a highly scalable cluster-based hierarchical trust management protocol for wireless sensor networks (WSNs) to effectively deal with selfish or malicious nodes. Unlike prior work, we consider multidimensional trust attributes derived from communication and social networks to evaluate the overall trust of a sensor node. By means of a novel probability model, we describe a heterogeneous WSN comprising a large number of sensor nodes with vastly different social and quality of service (QoS) behaviors with the objective to yield "ground truth" node status. This serves as a basis for validating our protocol design by comparing subjective trust generated as a result of protocol execution at runtime against objective trust obtained from actual node status. To demonstrate the utility of our hierarchical trust management protocol, we apply it to trust-based geographic routing and trust-based intrusion detection. For each application, we identify the best trust composition and formation to maximize application performance. Our results indicate that trust-based geographic routing approaches the ideal performance level achievable by flooding-based routing in message delivery ratio and message delay without incurring substantial message overhead. For trust-based intrusion detection, we discover that there exists an optimal trust threshold for minimizing false positives and false negatives. Furthermore, trust-based intrusion detection outperforms traditional anomaly-based intrusion detection approaches in both the detection probability and the false positive probability.
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paper_title: ReTrust: Attack-Resistant and Lightweight Trust Management for Medical Sensor Networks

paper_content:

Wireless medical sensor networks (MSNs) enable ubiquitous health monitoring of users during their everyday lives, at health sites, without restricting their freedom. Establishing trust among distributed network entities has been recognized as a powerful tool to improve the security and performance of distributed networks such as mobile ad hoc networks and sensor networks. However, most existing trust systems are not well suited for MSNs due to the unique operational and security requirements of MSNs. Moreover, similar to most security schemes, trust management methods themselves can be vulnerable to attacks. Unfortunately, this issue is often ignored in existing trust systems. In this paper, we identify the security and performance challenges facing a sensor network for wireless medical monitoring and suggest it should follow a two-tier architecture. Based on such an architecture, we develop an attack-resistant and lightweight trust management scheme named ReTrust. This paper also reports the experimental results of the Collection Tree Protocol using our proposed system in a network of TelosB motes, which show that ReTrust not only can efficiently detect malicious/faulty behaviors, but can also significantly improve the network performance in practice.
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paper_title: ZoneTrust: Fast Zone-Based Node Compromise Detection and Revocation in Wireless Sensor Networks Using Sequential Hypothesis Testing

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Due to the unattended nature of wireless sensor networks, an adversary can physically capture and compromise sensor nodes and then mount a variety of attacks with the compromised nodes. To minimize the damage incurred by the compromised nodes, the system should detect and revoke them as soon as possible. To meet this need, researchers have recently proposed a variety of node compromise detection schemes in wireless ad hoc and sensor networks. For example, reputation-based trust management schemes identify malicious nodes but do not revoke them due to the risk of false positives. Similarly, software-attestation schemes detect the subverted software modules of compromised nodes. However, they require each sensor node to be attested periodically, thus incurring substantial overhead. To mitigate the limitations of the existing schemes, we propose a zone-based node compromise detection and revocation scheme in wireless sensor networks. The main idea behind our scheme is to use sequential hypothesis testing to detect suspect regions in which compromised nodes are likely placed. In these suspect regions, the network operator performs software attestation against sensor nodes, leading to the detection and revocation of the compromised nodes. Through quantitative analysis and simulation experiments, we show that the proposed scheme detects the compromised nodes with a small number of samples while reducing false positive and negative rates, even if a substantial fraction of the nodes in the zone are compromised. Additionally, we model the detection problem using a game theoretic analysis, derive the optimal strategies for the attacker and the defender, and show that the attacker's gain from node compromise is greatly limited by the defender when both the attacker and the defender follow their optimal strategies.
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paper_title: An Iterative Algorithm for Trust Management and Adversary Detection for Delay-Tolerant Networks

paper_content:

Delay/Disruption Tolerant Networks (DTNs) have been identified as one of the key areas in the field of wireless communication, wherein sparseness and delay are particularly high. They are emerging as a promising technology in vehicular, planetary/interplanetary, military/tactical, disaster response, underwater and satellite networks. DTNs are characterized by large end-to-end communication latency and the lack of end-to-end path from a source to its destination. These characteristics pose several challenges to the security of DTNs. Especially, Byzantine attacks in which one or more legitimate nodes have been compromised and fully controlled by the adversary can give serious damages to the network in terms of latency and data availability. Using reputation-based trust management systems is shown to be an effective way to handle the adversarial behavior in Mobile Ad hoc Networks (MANETs). However, because of the unique characteristics of DTNs, those traditional techniques do not apply to DTNs. Our main objective in this paper is to develop a robust trust mechanism and an efficient and low cost malicious node detection technique for DTNs. Inspired by our recent results on reputation management for online systems and e-commerce, we develop an iterative malicious node detection mechanism for DTNs referred as ITRM. The proposed scheme is a graph-based iterative algorithm motivated by the prior success of message passing techniques for decoding low-density parity-check codes over bipartite graphs. Applying ITRM to DTNs for various mobility models, we observed that the proposed iterative reputation management scheme is far more effective than well-known reputation management techniques such as the Bayesian framework and EigenTrust. Further, we concluded that the proposed scheme provides high data availability and packet-delivery ratio with low latency in DTNs under various adversary attacks which attempt to both undermine the trust and detection scheme and the packet delivery protocol.
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paper_title: Trust-Aware Query Processing in Data Intensive Sensor Networks

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We propose an approach to trust management in data intensive sensor networks (DISN) based on subjective logic. We demonstrate that under given requirements for trustworthiness of data collected from sensors, the best sensor query processing strategy in the sense of time and energy efficiency can be considerably different from the strategies generated without trustworthiness requirements.
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paper_title: A Novel Approach to Trust Management in Unattended Wireless Sensor Networks

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Unattended Wireless Sensor Networks (UWSNs) are characterized by long periods of disconnected operation and fixed or irregular intervals between sink visits. The absence of an online trusted third party implies that existing WSN trust management schemes are not applicable to UWSNs. In this paper, we propose a trust management scheme for UWSNs to provide efficient and robust trust data storage and trust generation. For trust data storage, we employ a geographic hash table to identify storage nodes and to significantly decrease storage cost. We use subjective logic based consensus techniques to mitigate trust fluctuations caused by environmental factors. We exploit a set of trust similarity functions to detect trust outliers and to sustain trust pollution attacks. We demonstrate, through extensive analyses and simulations, that the proposed scheme is efficient, robust and scalable.
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paper_title: A Novel Trust-Aware Geographical Routing Scheme for Wireless Sensor Networks

paper_content:

Wireless sensor networks are vulnerable to a wide set of security attacks, including those targeting the routing protocol functionality. The applicability of legacy security solutions is disputable (if not infeasible), due to severe restrictions in node and network resources. Although confidentiality, integrity and authentication measures assist in preventing specific types of attacks, they come at high cost and, in most cases, cannot shield against routing attacks. To face this problem, we propose a secure routing protocol which adopts the geographical routing principle to cope with the network dimensions, and relies on a distributed trust model for the detection and avoidance of malicious neighbours. A novel function which adaptively weights location, trust and energy information drives the routing decisions, allowing for shifting emphasis from security to path optimality. The proposed trust model relies on both direct and indirect observations to derive the trustworthiness of each neighboring node, while it is capable of defending against an increased set of routing attacks including attacks targeting the indirect trust management scheme. Extensive simulation results reveal the advantages of the proposed model.
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Title: Systematic Design of Trust Management Systems for Wireless Sensor Networks: A Review

Section 1: INTRODUCTION
Description 1: Provide an introduction to Wireless Sensor Networks (WSNs), their vulnerabilities, and the relevance of trust management in overcoming these vulnerabilities.

Section 2: BACKGROUND AND PRELIMINARIES
Description 2: Outline the background and fundamental concepts related to WSNs and trust management, highlighting the need for trust management over traditional security methods.

Section 3: TRUST MODELS
Description 3: Discuss various trust models used by researchers to estimate trust and counteract malicious nodes within the network.

Section 4: TRUST MANAGEMENT APPLICATIONS
Description 4: Describe applications supported by trust management, such as access control, key management, secure routing, data aggregation, and intrusion detection.

Section 5: TRUST MANAGEMENT SYSTEM DESIGN
Description 5: Explain the systematic design of the trust management system, detailing the components and their interactions.

Section 6: CONCLUSION
Description 6: Summarize the systematic design of trust management systems for WSNs and discuss potential future work for improving these systems.