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Trust and Fairness in Open, Distributed Systems

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Abstract

Information technology today is a vast body of knowledge that has found applications in most areas of human activity and thought. With the proliferation of the Internet and its various applications, the role of information technology in society has become vital and is rapidly increasing in importance. It can be said that the Internet has become intertwined with society; and with each new generation of Internet users, information technology becomes applied not only more widely, but also affects our society and personal lives more deeply. We are witnessing the birth of the real e-society.
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... king in real time by conditioning the currency-creation mechanism(s) under agreed upon dynamics of collective deliberation: for instance, through either quarterly or monthly deliberation rounds (Spain), during special events like participatory budgeting (Iceland) or daily, if the system allows for social remuneration operations (Finland and Milan).Wierzbicki, 2010) Putting together trust and the blockchain, the Freecoin Toolchain allows for the design and prototyping of systems aimed at managing social currency in a community, i.e. reputation in a decentralized fashion: for example by using micro-endorsements as collateral/backing of the underlying complementary currency (Spain), risk is spread e ...
... When applied to human users, Trust Management methods attempt to leverage the human capacity for trust or distrust. (Wierzbicki, 2010) Trust management can be seen as a symbol-based automation of social decisions related to trust, where social agents instruct their technical representations how to act while meeting technical representations of other agents. In the context of the D-CENT project, pilot communities are the very settlers of the rules governing the trust management system that they self-manage. ...
... see Winslett, 2003) where technical devices negotiate trust by selectively disclosing credentials, according to rules defined by social agents that they represent. (Wikipedia) As Smart Contracts are already indicating, in the future trust management may become yet another standard service of information security, such as authentication, authorization, privacy or integrity (Wierzbicki, 2010). Most Trust Management systems use simple computational representations of trust. ...
Technical Report
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D-CENT aims at developing large-scale collective platforms to support citizen empowerment. As shown by the preliminary considerations from the first round of interviews with alternative and complementary system managers in Spain, Finland and Iceland (D1.2 and D3.4), decentralised and privacy aware digital infrastructures are needed to allow institutions to integrate social feedback from the citizens, leveraging the potential of the extended society and social experts to improve democracy and many aspects of our society. In turn, the experimentation on the Digital Social Currency Pilots in D-CENT can be conceived as an open-source approach to decentralized complementary currency design, which becomes ever more relevant where pilot communities are already actively designing tools for collective engagement and decision making on monetary economic matters affecting their communities.
... As for B2C e-commerce, some trust models and reputation evaluation methods have been put forward [11,49,50]. Various researchers have paid special attention to computation models of trust and reputation for B2C e-commerce in recent years [14][15][16]25,[51][52][53][54]. It is important to take into account the dynamical factor in the processes of trust development and reputation evaluation. ...
... As for B2C e-commerce, some trust models and reputation evaluation methods have been put forward [11,49,50]. Various researchers have paid special attention to computation models of trust and reputation for B2C e-commerce in recent years14151625,51525354. It is important to take into account the dynamical factor in the processes of trust development and reputation evaluation. ...
Article
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Trust is one of the most important factors that influence the successful application of network service environments, such as e-commerce, wireless sensor networks, and online social networks. Computation models associated with trust and reputation have been paid special attention in both computer societies and service science in recent years. In this paper, a dynamical computation model of reputation for B2C e-commerce is proposed. Firstly, conceptions associated with trust and reputation are introduced, and the mathematical formula of trust for B2C e-commerce is given. Then a dynamical computation model of reputation is further proposed based on the conception of trust and the relationship between trust and reputation. In the proposed model, classical varying processes of reputation of B2C e-commerce are discussed. Furthermore, the iterative trust and reputation computation models are formulated via a set of difference equations based on the closed-loop feedback mechanism. Finally, a group of numerical simulation experiments are performed to illustrate the proposed model of trust and reputation. Experimental results show that the proposed model is effective in simulating the dynamical processes of trust and reputation for B2C e-commerce.
... A S a fundamental desired property of any systems [1], keeping a high level of efficiency and fairness is a common goal of distributed systems and networks. In many systems such as wireless ad hoc networks, clouds, and computer networks can be named in which fairness plays an important role [2]. In some applications such as distributed wireless networks, it is even a more serious problem due to the system complexity, the broadcast medium, and prob- lems such as hidden-node [3] and short-term unfairness [4]. ...
... Each server is limited by its capacity and cannot be serv- ing queues with rates higher than that. Hence, constraint (2) means that the sum of rates allocated by each server to its queues should be equal to the capacity/rate of that server, and constraint (3) also dictates that no allocated rate by any server can be negative. Fairness of an allocation vector obtained from solving problem (1)- (3) is calculated on the total amount of rate allocated to each queue by its servers, i.e. ˆ ...
Article
Maintaining efficiency and fairness is a challenging problem in distributed systems and networks. In this paper, we focus on distributed multi-server systems and networks in which each user may be allocated resources by different servers. Reemphasizing polling systems as abstractions of resource sharing systems, in this paper, first we introduce a multi-server polling system in which each server (resource) can poll (be allocated to) only a subset of queues (users) in the system to model a wide range of multi-server systems such as multihomed networks and cloud computing. Then, to obtain a fair resource allocation vector to queues, a network utility maximization problem with a general utility function is defined. Depending on the type of the utility function, the presented scheme can attain different kinds of fairness such as weighted proportional and max-min fairness. Although maintaining fairness is important in many applications, providing efficiency is also crucial. Hence, we present an efficient algorithm to convert the obtained fair resource allocation vector into a Markovian routing matrix to determine the polling order of queues. This algorithm is capable of improving performance measures such as delay variance and mitigating short-term unfairness by minimizing the probability of consecutive polling of the same queue. Two distributed schemes are presented to obtain fairness and efficiency in even highly dynamic and distributed environments. Effectiveness of the presented schemes is also studied through simulation and numerical evaluation. Our results show their success in attaining fairness and efficiency in dynamic multi-server distributed systems and networks.
... Mainly, the trust among the agents is a crucial factor. In the most abstract manner, trust is a relation between a trustor and a trustee in a context [20]. There are several kinds of trust. ...
... Expectancy trust is a subjective, context-dependent expectation that the trustee will choose a specific action in an encounter. Furthermore, dependency trust can be defined as the subjective, context-dependent extent to which the trustor is willing to depend on the trustee in a situation of uncertainty [20]. ...
Article
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During a negotiation, an agent must make several key decisions in order to achieve a profitable agreement. When the negotiation is carried out in a social context, agents can use persuasion, besides the traditional exchange of concessions. To carry out the persuasion and make concessions, the agents must employ resources that are usually scarce. For this reason, the agents should carefully decide which opponent they should persuade to maximise their profit, especially when the negotiation involves multiple parties. To make this decision, we propose that the agents should persuade the opponents with a high influence on the other agents involved in the negotiation. Therefore, we represent a negotiation context as a social influence maximization problem and solve it under a model that learns how influence flows in a network by analysing historical information. This allows an agent to determine what opponents exert the highest influence. Finally, the agent uses this information to decide which opponent to persuade during the negotiation. Experimental results showed that the agreement rate increased when agents applied this approach.
... A number of kinds of fairness have been identified in the literature: these are the distributive, the procedural and the retributive. Distributive fairness relates to the distribution of goods and other resources; procedural focuses on procedures leading to outcomes; and the retributive is a matter of rules violations and the severity of sanctions for them (Wierzbicki, 2010). ...
Article
Purpose An engaged workforce has never been more important than it is now. Research continues to reveal a strong link between engaged employees and employee performance. Consequently, different strategies continue to be developed to enhance employee engagement (EE) in organisations. Unfortunately, many of these strategies have not worked due to the lack of trust that some employees may have towards organisational leaders. Thus, it is argued that the first step in building an effective EE is building trust, which will erode all sorts of suspicion of the intention of leaders in the organisation. Unfortunately, the literature is not clear about how to build such trust, especially in developing countries where the organisational environment is much different from that in developed ones; making the applicability of models in the developed world quite difficulty in these countries. How can public sector leaders build trust in the organisations in an environment where informality appears to be the norm? The purpose of this paper is therefore to ascertain how trust can be built in public organisations. Design/methodology/approach In order to answer the research questions, as well as obtain in-depth understanding of what is being done, the authors used the mixed methods approach in the data collection for the paper. In using mixed method data collection, the authors took both quantitative and qualitative approaches. Both qualitative and quantitative data were, however, collected concurrently. This was done for the sake of convenience, as there is little study on how to build trust or, even, EE in the Ghanaian context. The authors set out to explore these issues, and the only way for the authors to do so was to undertake the data collection simultaneously. Findings The paper examined critically four main areas to help leadership build trust: credibility, fairness, respect and communication. The study shows that both managers and employees firmly believe in building trust. Leaders were able to discuss the efforts they make to ensure that issues concerning trust building are addressed. At the same time, employees also agreed on the need to strengthen these variables. Practical implications The research identifies areas on which both leadership and employees can continually work to help bridge the gap between them if public organisations are to reap the benefits of EE. The authors are convinced that if the issues discussed here are addressed, and parties work on them, individuals will succeed in their own areas, but so will the organisations, which in turn will help in the development of he country. Originality/value From a theoretical perspective, it extends the work on EE, and offers new insight into this emerging concept from a developing countries perspective, where informality in the public sector is common. Most of the research on trust and EE has been either qualitative or quantitative in nature. Using the mixed methods approach means the authors will be explaining how both can help us better understand the “how” in building trust in the public sector. Thus, the paper is one of the few papers that have used the mixed methods approach to examine how trust can be built in public organisations.
... II. RELATED WORK Fairness is a term discussed in many fields, most prominently in economics [4] and psychology [5]. However, fairness also became an important criterion in application of information technology [6] and especially in the area of scheduling algorithms [7] and resource allocation [8]. In this Section, a selection of work is presented that is concerned with the definitions and fields of application in the SG scenario. ...
Conference Paper
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The introduction of more and more local and distributed energy resources (DER) into the current centralized electrical grid poses new challenges to energy distribution. DERs are significantly smaller in production capabilities than central power plants and their production is highly fluctuating. This means that their influence on the electrical grid is difficult to plan for, especially in brown-out situations, when there is not enough energy available to supply all consumers. This work focuses on the subproblem of fair electricity distribution in brown-out phases. Currently, network segments are switched on and off in a round-robin manner, regardless if there are local producers in these segments or not. However, enabling segments that include local producers more often would improve the overall amount of energy available during the brown-out phases, and thus, this measure would increase the number of supplied consumers. We propose new algorithms that leverage the power of local producers, but still keep a fair energy distribution for all consumers. Therefore, we evolve the current notion of fairness to improve the overall quality of service by taking into account equal supply times as well as maximizing the number of supplied consumers. The proposed algorithms are compared to the current state of the art approach in the German electrical grid. Therefore, extensive simulations based on real-world lowvoltage residential area networks were conducted. The results indicate an improved quality of service during brown-out phases. Moreover, the proposed method is not limited to low-voltage residential areas, but also applies to all hierarchy levels of the energy grid, ranging from the distribution grid down to future households implementing smart grid technologies.
... One could argue that running open-source (thus freely modifiable) code could lead to lesser trust in other SPTs. Mechanisms such as using signed code, or managing social trust [63] and reputation [151], could be used when deciding which SPTs to trust during a global computation. Adapting recommendation system algorithms to global computations provides an interesting research challenge. ...
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This document will focus on my core computer science research since 2010, covering the topic of data management and privacy. More speci cally, I will present the following topics : -ˆ A new paradigm, called Trusted Cells for privacy-centric personal data management based on the Asymmetric Architecture composed of trusted or open (low power) distributed hardware devices acting as personal data servers and a highly powerful, highly available supporting server, such as a cloud. (Chapter 2). ˆ- Adapting aggregate data computation techniques to the Trusted Cells environment, with the example of Privacy-Preserving Data Publishing (Chapter 3). - Minimizing the data that leaves a Trusted Cell, i.e. enforcing the general privacy principle of Limited Data Collection (Chapter 4). This document contains only results that have already been published. As such, rather than focus on the details and technicalities of each result, I have tried to provide an easy way to have a global understanding of the context behind the work, explain the problematic of the work, and give a summary of the main scienti c results and impact.
Chapter
This chapter looks at the issues that social machines raise about privacy, trust and ethics. The chapter begins by surveying the ethical significance of the various roles that are created by social machines, including the individual participant and the designer, and looks at the rights and duties that the occupants of these roles have. Social machines are considered as a particular type of social enterprise or project. The necessity for social machines to generate trust, and how that might impact the wider ethical status of social machines, is also considered. A type of ethical functionalism is described in which the flourishing of the social machine is taken as the basic requirements of ethics considered only from within the machine, not taking into account the outside content. Attitudes towards data and algorithms are considered, and means to render flows of data transparent are discussed, as means of putting social machine participants in control. Such means include privacy indicators, personal data stores and the X-Ray Refine system that explains data flows from a user’s smartphone. The ways in which people use technology to present themselves in certain ways (informational self-determination) are studied, and some experiments with social technologies that could aid informational self-determination are reported. In a final section, the specific and sensitive case of healthcare social machines is surveyed, including looking at areas where data use has a social aspect, such as participatory digital surveillance, quantified patient and social palliative care. Modelling social aspects of institutional procedures in the medical space is also considered, taking the examples of integrated care pathways and data safe havens.
Conference Paper
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Technical Report
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The di.me project aims at integrating all personal data in a personal information sphere by a single, user-controlled point of access: the di.me userware. This tool shall be a user-controlled personal service providing intelligent personal information management and is targeted on integrating social web systems and communities. It realises a decentral communication to avoid external data storage and undesired data disclose. Calculating trust in order to give valuable privacy recommendations is an increasing need in pervasive environments, especially when also considering context information (e. g. location information, nearby people). The developed di.me userware should support the user not only by helping in managing the personal information but also by giving valueable recommendations and warnings concerning the (unintended) disclosure of sensitive information to other, possibly untrusted, parties. In this deliverable we present concepts to measure and establish multidimensional trust metrics, specially tailored to the end-users’ needs in digital.me. Furthermore it includes usability and reliable interaction aspects. Thereby, information obtained from the context could represent a separate dimension in the trust metric. A special focus is the correctness and robustness of a suggested trust metric towards meaningful privacy recommendations for our scenarios. The deliverable is strongly connected to WP3 (especially task 3.4) and also an important component of the intelligent user interface (WP5), which will present the resulting warnings to the user. The suggested metric could help to avoid manipulations and attacks based on fundamental requirements for situational trust, by giving meaningful warnings and prove awareness of possible risks to the user. The metric supports dynamic and (semi-)automatic trust extensions and migration (e.g. using recommended trust settings and preferences). Among the planned future work is the improvement of trust calculation by taking into consideration presence history of persons and locations, in order to increase the accuracy of our base trust value. Developed concepts envisage meaningful and strong robustness against manipulations (by intentional or unintentional misusage), in order to reach representative evaluations. The involvement of a large number of end-users implies supporting different trust needs and interpretations, as addressed in section 1.2.7 of the DoW.
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