• Journal of Internet Computing and Services
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• v.8 no.4
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• pp.137-147
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• 2007

As Web-based online communities are rapidly growing, the agents in social groups need to know their measurable belief of trust for safe andsuccessful interactions. In this paper, we propose a computational model of trust resulting from available feedbacks in online communities. The notion of trust can be defined as an aggregation of consensus given a set of past interactions. The averagetrust of an agent further represents the center of gravity of the distribution of its trustworthiness and untrustworthiness. And then, we precisely describe the relationship between reputation, trust, and averagetrust through a concrete example of their computations. We apply our trust model to online internet settings in order to show how trust mechanisms are involved in a rational decision-making of the agents.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.4
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• pp.547-559
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• 2010

As web-based online communities are rapidly growing, the agents in the communities need to know their measurable belief of trust for safe and successful interactions. In this paper, we propose a computational model of trust resulting from available feedbacks in online communities. The notion of trust can be defined as an aggregation of consensus given a set of past interactions. The average trust of an agent further represents the center of gravity of the distribution of its trustworthiness and untrustworthiness. Furthermore, we precisely describe the relationships among reputation, trust and average trust through concrete examples showing their computations. We apply our trust model to online social networks in order to show how trust mechanisms are involved in the rational purchasing decision-making of buyers and sellers, and we summarize our simulation results.

• Journal of KIISE:Information Networking
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• v.35 no.1
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• pp.76-90
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• 2008

Wireless sensor networks are expected to play a vital role in the upcoming age of ubiquitous computing such as home environmental, industrial, and military applications. Compared with the vivid utilization of the sensor networks, however, security and privacy issues of the sensor networks are still in their infancy because unique challenges of the sensor networks make it difficult to adopt conventional security policies. Especially, node compromise is a critical threat because a compromised node can drain out the finite amount of energy resources in battery-powered sensor networks by launching various insider attacks such as a false data injection. Even cryptographic authentication mechanisms and key management schemes cannot suggest solutions for the real root of the insider attack from a compromised node. In this paper, we propose a novel trust-based secure aggregation scheme which identifies trustworthiness of sensor nodes and filters out false data of compromised nodes to make resilient sensor networks. The proposed scheme suggests a defensible approach against the insider attack beyond conventional cryptographic solutions. The analysis and simulation results show that our aggregation scheme using trust evaluation is more resilient alternative to median.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.1
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• pp.5-23
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• 2012

Nowadays, most researchers and manufacturers always pay attention on wireless sensor networks (WSNs) due to its potential applications in many regions such as military, industrial and civilian areas. WSNs are the basic components of Internet of Things (IoT) and the key to machine-to-machine communications and the future Internet. Also, the security is an essential element for deploying WSNs. Recently the concept of trust-based mechanism was proposed in WSNs such as traditional cryptographic and authentication mechanisms. However, there is lack a survey on trust management for WSNs, IoT even future Internet. In this paper, we discuss the concept and potential application areas of trust management for WSNs and IoT worlds. Furthermore, we survey different trust management issues (i.e., cluster, aggregation, reputation). Finally, future research directions with respect to trust management in WSNs and future IoT world are provided. We give not only simple WSNs for IoT environments but also a simulated bootstrap platform to provide the discussion of open challenges and solutions for deploying IoT in Future Internet.

• Journal of Information Technology Applications and Management
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• v.9 no.1
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• pp.127-142
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• 2002

This study examines various factors which influence the degree of Participation In B to B e-Marketplace. Based on literature review, six factors such as Information provision, IT infrastructure, trust, aggregation, new customer creation, and matching are identified. To collect the empirical data, survey methodology has been utilized. A total of 32 companies have returned completed responses. The results of analysis show high interdependencies between six factors and the degree of participation in e-Marketplace. In particular, aggregation is found to be the most influential factor. Additional analysis reveals that firms participating highly in e-Marketplace recognize aggregation and new customer creation the most important factors while less participating firms see IT infrastructure more important.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.3
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• pp.1119-1143
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• 2014

Lightweight trust mechanism with lightweight cryptographic primitives has emerged as an important mechanism in resource constraint wireless sensor based mobile devices. In this work, outlier detection in lightweight Mobile Ad-hoc NETworks (MANETs) is extended to create the space of reliable trust cycle with anomaly detection mechanism and minimum energy losses [1]. Further, system is tested against outliers through detection ratios and anomaly scores before incorporating virtual programmable nodes to increase the efficiency. Security in proposed system is verified through ProVerif automated toolkit and mathematical analysis shows that it is strong against bad mouthing and on-off attacks. Performance of proposed technique is analyzed over different MANET routing protocols with variations in number of nodes and it is observed that system provide good amount of throughput with maximum of 20% increase in delay on increase of maximum of 100 nodes. System is reflecting good amount of scalability, optimization of resources and security. Lightweight modeling and policy analysis with lightweight cryptographic primitives shows that the intruders can be detection in few milliseconds without any conflicts in access rights.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.4
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• pp.2171-2195
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• 2017

When purchasing an online product, a customer tends to be influenced strongly by its reputation, the aggregation of other customers' ratings on it. The reputation, however, is not always trustable since it can be manipulated easily by attackers who intentionally give unfair ratings to their target products. In this paper, we first address identifying trustable users who tend to give fair ratings to products in online rating systems and then propose a method of computing true reputation of a product by aggregating only those trustable users' ratings. In order to identify the trustable users, we list some candidate features that seem related significantly to the trustworthiness of users and verify the robustness of each of the features through extensive experiments. By finding and exploiting these robust features, we are able to identify trustable users and to compute true reputation effectively and efficiently based on fair ratings of those trustable users.

• Korean Journal of Labor Studies
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• v.19 no.1
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• pp.65-104
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• 2013

This study aims to examine the intermediary roles of employee performance between high performance work system (HPWS) and its operational performance on the resource based view. Taking into account the unit of analysis, this study used a hierarchical linear modeling analysis in order to test rigorously the association between HPWS at the organisational level and employee performance at the individual level. For this empirical test, Human Capital Corporate Panel (HCCP) data including 316 firms and 7,872 respondents (including 923 team leaders) were used. To meet the unit of analysis and test the mediation effect, data at the individual and team level were aggregated into the organisational level. The empirical results show that HPWS have a positive impact on operational performance as well as employee performance such as job satisfaction, organisational commitment and organisational trust. Regarding the mediation effect, job satisfaction and organisational trust mediate between HPWS and operational performance. Theoretical implications are discussed in conclusion.

• International Journal of Computer Science & Network Security
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• v.23 no.8
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• pp.121-136
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• 2023

Wireless Sensor Networks (WSNs) have many potential applications and unique challenges. Some problems of WSNs are: severe resources' constraints, low reliability and fault tolerant, low throughput, low scalability, low Quality of Service (QoS) and insecure operational environments. One significant solution against mentioned problems is hierarchical and clustering-based multipath routing. But, existent algorithms have many weaknesses such as: high overhead, security vulnerabilities, address-centric, low-scalability, permanent usage of optimal paths and severe resources' consumption. As a result, this paper is proposed an energy-aware, congestion-aware, location-based, data-centric, scalable, hierarchical and clustering-based multipath routing algorithm based on Numerical Taxonomy technique for homogenous WSNs. Finally, performance of the proposed algorithm has been compared with performance of LEACH routing algorithm; results of simulations and statistical-mathematical analysis are showing the proposed algorithm has been improved in terms of parameters like balanced resources' consumption such as energy and bandwidth, throughput, reliability and fault tolerant, accuracy, QoS such as average rate of packet delivery and WSNs' lifetime.

• Journal of KIISE
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• v.42 no.10
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• pp.1286-1293
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• 2015

Most e-marketplaces build a reputation system that provides potential buyers with reputation scores of sellers in order for buyers to identify the sellers that are more reliable and trustworthy. The reputation scores are computed based on the aggregation of buyers' ratings. However, when these ratings are used to compute the reputation scores, the existing reputation systems do not make a distinction according to the following two criteria: the capability of the seller and the quality of an item. We claim that a reputation system needs to separate the two criteria in order to provide more precise information about the seller. In this paper, we propose a method to compute seller's reputation by separating the rating into the seller's score and the item's score. The proposed method computes the reputation of the seller's capability by using only the 'seller's score' and helps potential buyers to find reliable sellers who provide fast delivery and better service. In experiments, we propose a simulation strategy that reflects the real life of an E-marketplace and verify the effectiveness of our method by using the generated simulation data.