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The beta reputation system

by Audun Jøsang, Roslan Ismail - In Proceedings of the 15th Bled Conference on Electronic Commerce , 2002
"... 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 ..."
Abstract - Cited by 364 (18 self) - Add to MetaCart
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. 1

TRAVOS: Trust and reputation in the context of inaccurate information sources

by W. T. Luke Teacy, Jigar Patel, Nicholas R. Jennings, Michael Luck - Journal of Autonomous Agents and Multi-Agent Systems , 2006
"... Abstract. In many dynamic open systems, agents have to interact with one another to achieve their goals. Here, agents may be self-interested and when trusted to perform an action for another, may betray that trust by not performing the action as required. In addition, due to the size of such systems ..."
Abstract - Cited by 145 (16 self) - Add to MetaCart
Abstract. In many dynamic open systems, agents have to interact with one another to achieve their goals. Here, agents may be self-interested and when trusted to perform an action for another, may betray that trust by not performing the action as required. In addition, due to the size of such systems, agents will often interact with other agents with which they have little or no past experience. There is therefore a need to develop a model of trust and reputation that will ensure good interactions among software agents in large scale open systems. Against this background, we have developed TRAVOS (Trust and Reputation model for Agent-based Virtual OrganisationS) which models an agent’s trust in an interaction partner. Specifically, trust is calculated using probability theory taking account of past interactions between agents, and when there is a lack of personal experience between agents, the model draws upon reputation information gathered from third parties. In this latter case, we pay particular attention to handling the possibility that reputation information may be inaccurate. 1
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A Survey of Trust in Computer Science and the Semantic Web

by Donovan Artz, Yolanda Gil , 2007
"... Trust is an integral component in many kinds of human interaction, allowing people to act under uncertainty and with the risk of negative consequences. For example, exchanging money for a service, giving access to your property, and choosing between conflicting sources of information all may utilize ..."
Abstract - Cited by 142 (3 self) - Add to MetaCart
Trust is an integral component in many kinds of human interaction, allowing people to act under uncertainty and with the risk of negative consequences. For example, exchanging money for a service, giving access to your property, and choosing between conflicting sources of information all may utilize some form of trust. In computer science, trust is a widelyused term whose definition differs among researchers and application areas. Trust is an essential component of the vision for the Semantic Web, where both new problems and new applications of trust are being studied. This paper gives an overview of existing trust research in computer science and the Semantic Web.

A Survey of Attack and Defense Techniques for Reputation Systems

by Kevin Hoffman, David Zage, Cristina Nita-rotaru
"... Reputation systems provide mechanisms to produce a metric encapsulating reputation for a given domain for each identity within the system. These systems seek to generate an accurate assessment in the face of various factors including but not limited to unprecedented community size and potentially ad ..."
Abstract - Cited by 104 (3 self) - Add to MetaCart
Reputation systems provide mechanisms to produce a metric encapsulating reputation for a given domain for each identity within the system. These systems seek to generate an accurate assessment in the face of various factors including but not limited to unprecedented community size and potentially adversarial environments. We focus on attacks and defense mechanisms in reputation systems. We present an analysis framework that allows for general decomposition of existing reputation systems. We classify attacks against reputation systems by identifying which system components and design choices are the target of attacks. We survey defense mechanisms employed by existing reputation systems. Finally, we analyze several landmark systems in the peer-to-peer domain, characterizing their individual strengths and weaknesses. Our work contributes to understanding 1) which design components of reputation systems are most vulnerable, 2) what are the most appropriate defense mechanisms and 3) how these defense mechanisms can be integrated into existing or future reputation systems to make them resilient to attacks.
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Trust Network Analysis with Subjective Logic

by Audun Jøsang, Touhid Bhuiyan - In Proceedings of the 29th Australasian Computer Science Conference (ACSC2006), CRPIT Volume 48 , 2006
"... Trust network analysis with subjective logic (TNA-SL) simplifies complex trust graphs into series-parallel graphs by removing the most uncertain paths to obtain a canoni-cal graph. This simplification could in theory cause loss of information and thereby lead to sub-optimal results. This paper descr ..."
Abstract - Cited by 97 (12 self) - Add to MetaCart
Trust network analysis with subjective logic (TNA-SL) simplifies complex trust graphs into series-parallel graphs by removing the most uncertain paths to obtain a canoni-cal graph. This simplification could in theory cause loss of information and thereby lead to sub-optimal results. This paper describes a new method for trust network analysis which is considered optimal because it does not require trust graph simplification, but instead uses edge splitting to obtain a canonical graph. The new method is compared with TNA-SL, and our simulation shows that both methods produce equal results. This indicates that TNA-SL in fact also represents an optimal method for trust network analy-sis and that the trust graph simplification does not affect the result. 1

QoS-based service selection and ranking with trust and reputation management

by Le-hung Vu, Manfred Hauswirth, Karl Aberer - in Proceedings of the Cooperative Information System Conference (CoopIS’05 , 2005
"... Abstract. QoS-based service selection mechanisms will play an essential role in service-oriented architectures, as e-Business applications want to use services that most accurately meet their requirements. Standard approaches in this field typically are based on the prediction of services’ performan ..."
Abstract - Cited by 78 (3 self) - Add to MetaCart
Abstract. QoS-based service selection mechanisms will play an essential role in service-oriented architectures, as e-Business applications want to use services that most accurately meet their requirements. Standard approaches in this field typically are based on the prediction of services’ performance from the quality advertised by providers as well as from feedback of users on the actual levels of QoS delivered to them. The key issue in this setting is to detect and deal with false ratings by dishonest providers and users, which has only received limited attention so far. In this paper, we present a new QoS-based semantic web service selection and ranking solution with the application of a trust and reputation management method to address this problem. We will give a formal description of our approach and validate it with experiments which demonstrate that our solution yields high-quality results under various realistic cheating behaviors. 1
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Coping with inaccurate reputation sources: Experimental analysis of a probabilistic trust model

by W. T. Luke Teacy, Jigar Patel, Nicholas R. Jennings, Michael Luck, Multiagent Systems - In AAMAS ’05: Proceedings of the fourth international joint conference on Autonomous agents and multiagent systems , 2005
"... This research aims to develop a model of trust and reputation that will ensure good interactions amongst software agents in large scale open systems. The following are key drivers for our model: (1) agents may be self-interested and may provide false accounts of experiences with other agents if it i ..."
Abstract - Cited by 67 (7 self) - Add to MetaCart
This research aims to develop a model of trust and reputation that will ensure good interactions amongst software agents in large scale open systems. The following are key drivers for our model: (1) agents may be self-interested and may provide false accounts of experiences with other agents if it is beneficial for them to do so; (2) agents will need to interact with other agents with which they have little or no past experience. Against this background, we have developed TRAVOS (Trust and Reputation model for Agentbased Virtual OrganisationS) which models an agent’s trust in an interaction partner. Specifically, trust is calculated using probability theory taking account of past interactions between agents. When there is a lack of personal experience between agents, the model draws upon reputation information gathered from third parties. In this latter case, we pay particular attention to handling the possibility that reputation information may be inaccurate.
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Recruitment Framework for Participatory Sensing Data Collections

by Sasank Reddy, Deborah Estrin, Mani Srivastava
"... Abstract. Mobile phones have evolved from devices that are just used for voice and text communication to platforms that are able to capture and transmit a range of data types (image, audio, and location). The adoption of these increasingly capable devices by society has enabled a potentially pervasi ..."
Abstract - Cited by 67 (2 self) - Add to MetaCart
Abstract. Mobile phones have evolved from devices that are just used for voice and text communication to platforms that are able to capture and transmit a range of data types (image, audio, and location). The adoption of these increasingly capable devices by society has enabled a potentially pervasive sensing paradigm- participatory sensing. A coordinated participatory sensing system engages individuals carrying mobile phones to explore phenomena of interest using in situ data collection. For participatory sensing to succeed, several technical challenges need to be solved. In this paper, we discuss one particular issue: developing a recruitment framework to enable organizers to identify well-suited participants for data collections based on geographic and temporal availability as well as participation habits. This recruitment system is evaluated through a series of pilot data collections where volunteers explored sustainable processes on a university campus.
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A trust evaluation framework in distributed networks: vulnerability analysis and defense against attacks

by Yan Lindsay Sun, K. J. Ray Liu - in Proc. INFOCOM, 2006 , 2006
"... Abstract — The performance of distributed networks depends on collaboration among distributed entities. To enhance security in distributed networks, such as ad hoc networks, it is important to evaluate the trustworthiness of participating entities since trust is the major driving force for collabora ..."
Abstract - Cited by 66 (9 self) - Add to MetaCart
Abstract — The performance of distributed networks depends on collaboration among distributed entities. To enhance security in distributed networks, such as ad hoc networks, it is important to evaluate the trustworthiness of participating entities since trust is the major driving force for collaboration. In this paper, we present a framework to quantitatively measure trust, model trust propagation, and defend trust evaluation systems against malicious attacks. In particular, we address the fundamental understanding of trust, quantitative trust metrics, mathematical properties of trust, dynamic properties of trust, and trust models. The attacks against trust evaluation are identified and defense techniques are developed. The proposed trust evaluation system is employed in ad hoc networks for securing ad hoc routing and assisting malicious node detection. The implementation is fully distributed. Simulations show that the proposed system can significantly improve network throughput as well as effectively detect malicious behaviors in ad hoc networks. Further, extensive simulations are performed to illustrate various attacks and the effectiveness of the proposed defense techniques. I.
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Can We Manage Trust?

by Audun Jøsang, Claudia Keser, Theo Dimitrakos - Proceedings of the Third International Conference on Trust Management (iTrust), Versailes , 2005
"... The term trust management suggests that trust can be managed, for example by creating trust, by assessing trustworthiness, or by determining optimal decisions based on specific levels of trust. The problem to date is that trust management in online environments is a diverse and ill defined discip ..."
Abstract - Cited by 59 (2 self) - Add to MetaCart
The term trust management suggests that trust can be managed, for example by creating trust, by assessing trustworthiness, or by determining optimal decisions based on specific levels of trust. The problem to date is that trust management in online environments is a diverse and ill defined discipline. In fact, the term trust management is being used with very different meanings in different contexts. This paper examines various approaches related to online activities where trust is relevant and where there is potential for trust management.
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