@phdthesis{Hofmann2022,
  author    = {Hofmann, Adrian},
  title     = {Challenges and Solution Approaches for Blockchain Technology},
  doi       = {10.25972/OPUS-28261},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-282618},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2022},
  abstract  = {The digital transformation facilitates new forms of collaboration between companies along the supply chain and between companies and consumers. Besides sharing information on centralized platforms, blockchain technology is often regarded as a potential basis for this kind of collaboration. However, there is much hype surrounding the technology due to the rising popularity of cryptocurrencies, decentralized finance (DeFi), and non-fungible tokens (NFTs). This leads to potential issues being overlooked. Therefore, this thesis aims to investigate, highlight, and address the current weaknesses of blockchain technology: Inefficient consensus, privacy, smart contract security, and scalability. First, to provide a foundation, the four key challenges are introduced, and the research objectives are defined, followed by a brief presentation of the preliminary work for this thesis. The following four parts highlight the four main problem areas of blockchain. Using big data analytics, we extracted and analyzed the blockchain data of six major blockchains to identify potential weaknesses in their consensus algorithm. To improve smart contract security, we classified smart contract functionalities to identify similarities in structure and design. The resulting taxonomy serves as a basis for future standardization efforts for security-relevant features, such as safe math functions and oracle services. To challenge privacy assumptions, we researched consortium blockchains from an adversary role. We chose four blockchains with misconfigured nodes and extracted as much information from those nodes as possible. Finally, we compared scalability solutions for blockchain applications and developed a decision process that serves as a guideline to improve the scalability of their applications. Building on the scalability framework, we showcase three potential applications for blockchain technology. First, we develop a token-based approach for inter-company value stream mapping. By only relying on simple tokens instead of complex smart-contracts, the computational load on the network is expected to be much lower compared to other solutions. The following two solutions use offloading transactions and computations from the main blockchain. The first approach uses secure multiparty computation to offload the matching of supply and demand for manufacturing capacities to a trustless network. The transaction is written to the main blockchain only after the match is made. The second approach uses the concept of payment channel networks to enable high-frequency bidirectional micropayments for WiFi sharing. The host gets paid for every second of data usage through an off-chain channel. The full payment is only written to the blockchain after the connection to the client gets terminated. Finally, the thesis concludes by briefly summarizing and discussing the results and providing avenues for further research.},
  subject      = {Blockchain},
  language  = {en}
}
@techreport{HermJaniesch2019,
  type      = {Working Paper},
  author    = {Herm, Lukas-Valentin and Janiesch, Christian},
  title     = {Anforderungsanalyse f{\"u}r eine Kollaborationsplattform in Blockchain-basierten Wertsch{\"o}pfungsnetzwerken},
  doi       = {10.25972/OPUS-18886},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-188866},
  year      = {2019},
  abstract  = {In our globalized world, companies operate on an international market. To concentrate on their main competencies and be more competitive, they integrate into supply chain networks. However, these potentials also bear many risks. The emergence of an international market also creates pressure from competitors, forcing companies to collaborate with new and unknown companies in dynamic supply chain networks. In many cases, this can cause a lack of trust as the application of illegal practices and the breaking of agreements through complex and nontransparent supply chain networks pose a threat. Blockchain technology provides a transparent, decentralized, and distributed means of chaining data storage and thus enables trust in its tamper-proof storage, even if there is no trust in the cooperation partners. The use of the blockchain also provides the opportunity to digitize, automate, and monitor processes within supply chain networks in real time. The research project "Plattform f{\"u}r das integrierte Management von Kollaborationen in Wertsch{\"o}pfungsnetzwerken" (PIMKoWe) addresses this issue. The aim of this report is to define requirements for such a collaboration platform. We define requirements based on a literature review and expert interviews, which allow for an objective consideration of scientific and practical aspects. An additional survey validates and further classifies these requirements as "essential", "optional", or "irrelevant". In total, we have derived a collection of 45 requirements from different dimensions for the collaboration platform. Employing these requirements, we illustrate a conceptual architecture of the platform as well as introduce a realistic application scenario. The presentation of the platform concept and the application scenario can provide the foundation for implementing and introducing a blockchain-based collaboration platform into existing supply chain networks in context of the research project PIMKoWe.},
  subject      = {Blockchain},
  language  = {de}
}
@techreport{BaumgartBredebachHermetal.2022,
  author    = {Baumgart, Michael and Bredebach, Patrick and Herm, Lukas-Valentin and Hock, David and Hofmann, Adrian and Janiesch, Christian and Jankowski, Leif Ole and Kampik, Timotheus and Keil, Matthias and Kolb, Julian and Kr{\"o}hn, Michael and Pytel, Norman and Schaschek, Myriam and St{\"u}bs, Oliver and Winkelmann, Axel and Zeiß, Christian},
  title     = {Plattform f{\"u}r das integrierte Management von Kollaborationen in Wertsch{\"o}pfungsnetzwerken (PIMKoWe)},
  editor    = {Winkelmann, Axel and Janiesch, Christian},
  issn      = {2199-0328},
  doi       = {10.25972/OPUS-29335},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-293354},
  pages     = {248},
  year      = {2022},
  abstract  = {Das Verbundprojekt „Plattform f{\"u}r das integrierte Management von Kollaborationen in Wertsch{\"o}pfungsnetzwerken" (PIMKoWe - F{\"o}rderkennzeichen „02P17D160") ist ein Forschungsvorhaben im Rahmen des Forschungsprogramms „Innovationen f{\"u}r die Produktion, Dienstleistung und Arbeit von morgen" der Bekanntmachung „Industrie 4.0 - Intelligente Kollaborationen in dynamischen Wertsch{\"o}pfungs-netzwerken" (InKoWe). Das Forschungsvorhaben wurde mit Mitteln des Bundesministeriums f{\"u}r Bildung und Forschung (BMBF) gef{\"o}rdert und durch den Projekttr{\"a}ger des Karlsruher Instituts f{\"u}r Technologie (PTKA) betreut. Ziel des Forschungsprojekts PIMKoWe ist die Entwicklung und Bereitstellung einer Plattforml{\"o}sung zur Flexibilisierung, Automatisierung und Absicherung von Kooperationen in Wertsch{\"o}pfungsnetzwerken des industriellen Sektors.},
  subject      = {Blockchain},
  language  = {de}
}