- Conference PaperPrivacy-preserving KYC on Ethereum(Proceedings of 1st ERCIM Blockchain Workshop 2018, 2018) Biryukov, Alex; Khovratovich, Dmitry; Tikhomirov, SergeiIdentity is a fundamental concept for the financial industry. In order to comply with regulation, financial institutions must verify the identity of their customers. Identities are currently handled in a centralized way, which diminishes users' control over their personal information and threats their privacy. Blockchain systems, especially those with support for smart contracts (e.g., Ethereum), are expected to serve as a basis of more decentralized systems for digital identity management. We propose a design of a privacy-preserving KYC scheme on top of Ethereum. It would let providers of financial services leverage the potential of blockchain technology to increase effciency of customer onboarding while complying with regulation and protecting users' privacy.
- Conference PaperEngineering sustainable blockchain applications(Proceedings of 1st ERCIM Blockchain Workshop 2018, 2018) Osterland, Thomas; Rose, ThomasBlockchain technology has attracted attention as emerging paradigm for business collaboration. Blockchain’s consensus mechanisms allow partners to cooperate in a business network. However, many applications reported in literature present merely a proof of concept from an engineering perspective. An industrialization of blockchain requires an engineering framework, which assures the sustainability of the application and in particular its network partnerships, i.e. each participant has to act as an active peer in the network rather than being a mere consumer with a wallet for participation in the blockchain. This paper presents the skeleton of such an engineering framework starting with an ideation of partnerships and collaboration patterns to clarify the incentives for participation via business model design for sustainable network operations towards the selection of an implementation platform for the business processes re-engineered. Moreover, an initial version of an interactive tool for community-oriented capturing of know-how about characteristics of blockchain platforms is presented.
- Conference PaperA Use Case Identification Framework and Use Case Canvas for identifying and exploring relevant Blockchain opportunities(Proceedings of 1st ERCIM Blockchain Workshop 2018, 2018) Klein, Sandra; Prinz, WolfgangBlockchain is a new, foundational technology with a vast amount of application possibilities. However, practitioners might not be aware of which use cases in their own business model might benefit from blockchain technology. To aid them in analyzing their business regarding blockchain suitability, this paper introduces a use case identification framework for blockchain and a use case canvas. In the development process they have been evaluated with internal and external reviews in order to offer the best possible guidance. In combination they offer an analysis framework to help practitioners decide which use cases they should take into account for blockchain technology, which characteristics these blockchain implementations would have, and which specific advantages they would offer.
- Conference PaperPrivacy by BlockChain Design: A BlockChain-enabled GDPR-compliant Approach for Handling Personal Data(Proceedings of 1st ERCIM Blockchain Workshop 2018, 2018) Wirth, Christian; Kolain, MichaelThis paper takes an initial step forward in bringing to life the certification mechanisms according to Art. 42 of the General Data Protection Regulation (GDPR). These newly established methods of legal specification act not only as a central vehicle for overcoming widely articulated and discussed legal challenges, but also as a sandbox for the much needed close collaboration between computer sciences and legal studies. In order to illustrate, for example, what data protection seals could look like in the future, the authors propose a methodology for "translating" legal requirements into technical guidelines: architectural blueprints designed using legal requirements. The purpose of these blueprints is to show developers how their solutions might comply with the principle of Privacy by Design (Art. 25 GDPR). To demonstrate this methodology, the authors propose an architectural blueprint that embodies the legal concept of the data subject’s consent (Art. 6 sec. 1 lit. a GDPR) and elevates best practice to a high standard of Privacy by Design. Finally, the authors highlight further legal problems concerning blockchain technology under the GDPR that will have to be addressed in order to achieve a comprehensive certification mechanism for Privacy by Blockchain Design in the future.
- Conference PaperDEFenD: A Secure and Privacy-Preserving Decentralized System for Freight Declaration(Proceedings of 1st ERCIM Blockchain Workshop 2018, 2018) Vos, Daniel; Overweel, Leon; Raateland, Wouter; Vos, Jelle; Bijman, Matthijs; Pigmans, Max; Erkin, ZekeriyaMillions of shipping containers filled with goods move around the world every day. Before such a container may enter a trade bloc, the customs agency of the goods’ destination country must ensure that it does not contain illegal or mislabeled goods. Due to the high volume of containers, customs agencies make a selection of containers to audit through a risk analysis procedure. Customs agencies perform risk analysis using data sourced from a centralized system that is potentially vulnerable to manipulation and malpractice. Therefore we propose an alternative: DEFenD, a decentralized system that stores data about goods and containers in a secure and privacy-preserving manner. In our system, economic operators make claims to the network about goods they insert into or remove from containers, and encrypt these claims so that they can only be read by the destination country’s customs agency. Economic operators also make unencrypted claims about containers with which they interact. Unencrypted claims can be validated by the entire network of customs agencies. Our key contribution is a data partitioning scheme and several protocols that enable such a system to utilize blockchain and its powerful validation principle, while also preserving the privacy of the involved economic operators. Using our protocol, customs agencies can improve their risk analysis and economic operators can get through customs with less delay. We also present a reference implementation built with Hyperledger Fabric and analyze to what extent our implementation meets the requirements in terms of privacy-preservation, security, scalability, and decentralization.
- Conference PaperDeveloping an Evaluation Framework for Blockchain in the Public Sector: The Example of the German Asylum Process(Proceedings of 1st ERCIM Blockchain Workshop 2018, 2018) Fridgen, Gilbert; Guggenmoos, Florian; Lockl, Jannik; Rieger, Alexander; Schweizer, AndreThe public sector presents several promising applications for blockchain technology. Global organizations and innovative ministries in countries such as Dubai, Sweden, Finland, the Netherlands, and Germany have recognized these potentials and have initiated projects to evaluate the adoption of blockchain technology. As these projects can have a far-reaching impact on crucial government services and processes, they should involve a particularly thorough evaluation. In this paper, we provide insights into the development of a framework to support such an evaluation for the German asylum process. We built this framework evolutionarily together with the Federal Office for Migration and Refugees. Its final version consists of three levels and eighteen categories of evaluation criteria across the technical, functional and legal domains and allows specifying use-case specific key performance indicators or knockout criteria.
- Conference PaperBlockchain for Education: Lifelong Learning Passport(Proceedings of 1st ERCIM Blockchain Workshop 2018, 2018) Gräther, Wolfgang; Kolvenbach, Sabine; Ruland, Rudolf; Schütte, Julian; Torres, Christof; Wendland, FlorianCertificates play an important role in education and in professional development in companies. Individual learning records become essential for people’s professional careers. It is therefore important that these records are stored in long-term available and tamper-proof ledgers. A blockchain records transactions in a verifiable and permanent way, therefore it is very suitable to store fingerprints of certificates or other educational items. Blockchain reveals forgery of certificates and it supports learning histories. In this paper, we present the Blockchain for Education platform as a practical solution for issuing, validating and sharing of certificates. At first, we describe the conceptual system overview and then we present in detail the platform implementation including management of certification authorities and certificates, smart contracts as well as services for certifiers, learners and third parties such as employers. Finally, we describe use cases and first evaluation results that we gathered from end user tests with certifiers and conclude with a discussion.
- Conference PaperOn Immutability of Blockchains(Proceedings of 1st ERCIM Blockchain Workshop 2018, 2018) Landerreche, Esteban; Stevens, MarcRecently we presented a single-party cryptographic timestamping mechanism based on proof-of-sequential-work, which we proved secure in the universal composability framework . This paper describes this construction and its security claims and uses it to construct a multi-party permissioned blockchain protocol and show that it achieves an immutability notion. Finally we discuss applications of this protocol, including unpermissioned blockchains, and how these may benefit.
- Conference PaperTechruption Consortium Blockchain – what it takes to run a blockchain together(Proceedings of 1st ERCIM Blockchain Workshop 2018, 2018) van Deventer, Oskar; Berkers, Frank; Vos, Mischa; Zandee, André; Vreuls, Tom; van Piggelen, Laurens; Blom, Alexander; Heeringa, Bas; Akdim, Saïd; van Helvoort, Paul; van de Weem, Leon; van de Ruit, DouweThis paper presents initial results of the Techruption Consortium Blockchain experiment. The purpose of the experiment is to learn what it takes to run a permissioned consortium blockchain infrastructure together, not only from a technical perspective, but also governance and business model. The experiment turned out to be surprisingly complex, running into buggy open-source software, extensive firewall and connectivity issues, a complex legal context, a plethora of governance issues, many business model alternatives, and an ever-present human resource limitation. Based on our experiences, we conclude that instead of developing dedicated technical infrastructure, governance and business models for each blockchain application individually, there is a need for a shared blockchain infrastructure with basic governance and business models to spur further innovation in blockchain applications and enabling technologies.
- Conference PaperTRADE: A Transparent, Decentralized Traceability System for the Supply Chain(Proceedings of 1st ERCIM Blockchain Workshop 2018, 2018) El Maouchi, Mourad; Ersoy, O˘guzhan; Erkin, ZekeriyaTraceability has become an increasingly important aspect of the supply chain in the last few years due to customer awareness as well as better planning and problem identification. Unfortunately, technological, legal, and organizational concerns limit the possibility to utilize a centralized system to achieve traceability. Trust is one of the most important factors preventing the appliance of a centralized system. Previous works provided several approaches to create a decentralized traceability system. However, these works do not state the feasibility of their work and its appliance for the supply chain. In this paper, we propose a fully transparent and decentralized traceability system for the supply chain, namely TRADE. The system leverages the actors and supply chain structure to achieve traceability. Moreover, consumers and other parties can view all the data in the system and verify the claims of actors on the products. The latter results in positive brand reputation and auditability.