Privacy Preservation & Security Solutions in Blockchain Network

Blockchain has seen exponential progress over the past few years, and today its usage extends well beyond cryptocurrencies. Its features, including openness, transparency, secure communication, difficult falsification, and multi-consensus, have made it one of the most valuable technology in the world. In most open blockchain platforms, any node can access the data on the blockchain, which leads to a potential risk of personal information leakage. So the issue of blockchain privacy and security is particularly prominent and has become an important research topic in the field of blockchain. This dissertation mainly summarizes my research on blockchain privacy and security protection issues throughout recent years. We first summarize the security and privacy vulnerabilities in the mining pools of traditional bitcoin networks and some possible protection measures. We then propose a new type of attack: coin hopping attack, in the case of multiple blockchains under an IoT environment. This attack is only feasible in blockchain-based IoT scenarios, and can significantly reduce the operational efficiency of the entire blockchain network in the long run. We demonstrate the feasibility of this attack by theoretical analysis of four different attack models and propose two possible solutions. We also propose an innovative hybrid blockchain crowdsourcing platform solution to settle the performance bottlenecks and various challenges caused by privacy, scalability, and verification efficiency problems of current blockchain-based crowdsourcing systems. We offer flexible task-based permission control and a zero-knowledge proof mechanism in the implementation of smart contracts to flexibly obtain different levels of privacy protection. By performing several tests on Ethereum and Hyperledger Fabric, EoS.io blockchains, the performance of the proposed platform consensus under different transaction volumes is verified. At last, we also propose further investigation on the topics of the privacy issues when combining AI with blockchain and propose some defense strategies

08491 Abstracts Collection -- Theoretical Foundations of Practical Information Security

From 30.11. to 05.12.2008, the Dagstuhl Seminar 08491 ``Theoretical Foundations of Practical Information Security \u27\u27 was held in Schloss Dagstuhl~--~Leibniz Center for Informatics. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

The Origins and the Evolution of Health Economics: a discipline by itself? Led by economists, practitioners or politics?

Health has become a dominant economic and political issue over the past 40 years, with nations experiencing rapid rises in health care spending, and the health sector presenting high levels of expansion, rationalization and organization. I describe how by the end of World War II, both the intellectual and financial resources were being made available to answer the emerging empiricallydriven questions for a new applied branch of economic analysis: Health Economics. I also discuss the driving forces for the evolution of this new field, while identifying two distinct paths in health economic thought: the first rising from a territory previously ploughed, namely by Mushkin (1962), and later developed by Grossman (1972; the second of which stemming from Arrow’s 1963 paper ‘Uncertainty and the Welfare Economics of Medical Care’, a singularity amongst his mathematical economics pearls. Blaug remarked, in 1998: “health economics would seem to be a perfect topic for heterodox dissent and yet, surprisingly enough, radical economists and Marxists have not on the whole been attracted to health economics”. My view is this could have been because “mathematical economists” stepped forward and challenged themselves to solve problems such an unorthodox market posed.Health Economics, Health Care Sector/ U.S. History, Social Welfare

A Property Rights Enforcement and Pricing Model for IIoT Data Marketplaces

학위논문(석사)--서울대학교 대학원 :공과대학 협동과정 기술경영·경제·정책전공,2019. 8. Jörn Altmann.The Industrial Internet of Things (IIoT) has become a valuable data source for products and services based on advanced data analytics. However, evidence suggests that industries are suffering a significant loss of value creation from insufficient IIoT data sharing. We argue that the limited utilization of the Sensing as a Service business model is caused by the economic and technological characteristics of sensor data, and the corresponding absence of applicable digital rights management models. Therefore, we propose a combined property rights enforcement and pricing model to solve the IIoT data sharing incentive problem.산업용 사물 인터넷 (IIoT) 데이터가 제품과 서비스를 위한 중요한 고급 데이터 소스로 여겨지고 있지만, 여전히 수 많은 기업들은 불충분한 산업용 사물 인터넷 데이터 공유 시스템으로 인하여 고충을 겪고 있다. 방대한 분량의 산업용 데이터가 제대로 거래되지 못하고 있으며, 이는 데이터의 커다란 가치 손실로 이어지고 있다. 본 연구에서는 서비스로서의 센싱 (Sensing as a Service) 비지니스 모델이 한정적으로 적용되고 있는 원인이 해당 정보의 경제적, 기술적 특징들을 반영하는 디지털 권리 시스템의 부재에 기인한다고 보고 있다. 따라서 본 연구에서는 산업용 사물 인터넷 데이터에 대한 지적재산권 집행 시스템과 데이터 가격산정 모델을 제안하여 산업용 사물 인터넷 데이터 공유 인센티브 문제를 해결하고자 한다.1 Introduction 1 1.1 Background 1 1.2 Problem Description 6 1.3 Research Objective and Question 8 1.4 Methodology 8 1.5 Contributions 9 1.6 Structure 10 2 Literature Review 11 2.1 Sensing as a Service 11 2.2 Economic Characteristics of IIoT Data 14 2.2.1 Property Rights of Data 18 2.2.2 Licensing of IIoT Data 23 2.3 IIoT Data Marketplaces 25 2.3.1 Use-cases and Value Propositions 30 2.3.2 Market Structures and Pricing Models 34 2.4 Digital Rights Management for IIoT 36 3 Model 44 3.1 Assumptions 45 3.2 Watermarking Technique 47 3.2.1 Function 48 3.2.2 Example 50 3.2.3 Robustness 51 3.3 Economic Reasoning 54 3.3.1 The Quality Gap 55 3.3.2 Cost of Watermarking (CoW) 57 3.3.3 Cost of Attacking (CoA) 58 4 Analytical Analysis 60 4.1 Equilibrium Between CoW and CoA 60 4.2 Determining the Optimal Quality Gap 62 4.3 Applicability of the Quality Gap Function 64 5 Conclusion 66 5.1 Summary 66 5.2 Discussion 66 6 Limitations and Future Research 68 References 70 Abstract (Korean) 79Maste

Examining the motivations for social entrepreneurship using Max Weber's typology of rationality

PURPOSE: This paper aims to utilize a framework from classic sociology – Max Weber’s Typology of Rationality – to understand the motivations for social entrepreneurship in responsible tourism in India. The critical role of the social entrepreneur in effecting the phenomenon of social entrepreneurship has been largely under-recognized. The authors seek to explore, develop and enhance Weber’s theoretical arguments in the context of the tourism industry. Design/methodology/approach The authors used a constructivism paradigm and Seidman’s (2006) Three Interview Series technique to obtain the narratives of two social entrepreneurs in India. Data were analyzed using a hybrid thematic coding procedure. FINDINGS: Findings indicate that there exists a dynamic interplay between the formal and substantive rationalities that underlie the behavior of social entrepreneurs. The authors also discuss how entrepreneurs draw upon their formal and substantive repertoires to create their identities through the simultaneous processes of apposition (“Me”) and opposition (“Not Me”). PRACTICAL IMPLICATIONS: The findings provide an important recognition of the impact of formal and substantive rationalities on the conceptualization, implementation and manifestation of social enterprise for a variety of stakeholders. ORIGINALITY/VALUE: This paper makes a significant contribution to understanding the why and the how of social entrepreneurship in responsible tourism. It provides a framework that can be widely applied to develop and enhance Weberian theory and further the understanding of the fundamental nature of human behavioral phenomena in tourism and beyond

Group key establishment protocols: Pairing cryptography and verifiable secret sharing scheme

Thesis (Master)--Izmir Institute of Technology, Computer Engineering, Izmir, 2013Includes bibliographical references (leaves: 97-103)Text in English; Abstract: Turkish and Englishx, 154 leavesThe aim of this study is to establish a common secret key over an open network for a group of user to be used then symmetrical secure communication between them. There are two methods of GKE protocol which are key agreement and key distribution. Key agreement is a mechanism whereby the parties jointly establish a common secret. As to key distribution, it is a mechanism whereby one of the parties creates or obtains a secret value and then securely distributes it to other parties. In this study, both methods is applied and analyzed in two different GKE protocols. Desirable properties of a GKE are security and efficiency. Security is attributed in terms of preventing attacks against passive and active adversary. Efficiency is quantified in terms of computation, communication and round complexity. When constructing a GKE, the challenge is to provide security and efficiency according to attributed and quantified terms. Two main cryptographic tools are selected in order to handle the defined challenge. One of them is bilinear pairing which is based on elliptic curve cryptography and another is verifiable secret sharing which is based on multiparty computation. In this thesis, constructions of these two GKE protocols are studied along with their communication models, security and efficiency analysis. Also, an implementation of four-user group size is developed utilizing PBC, GMP and OpenSSL Libraries for both two protocols