Yes / Smart contracts have recently attracted interest from diverse fields including law and finance. Ethereum in particular has grown rapidly to accommodate an entire ecosystem of contracts which run using its own crypto-currency. Smart contract developers can opt to verify their contracts so that any user can inspect and audit the code before executing the contract. However, the huge numbers of deployed smart contracts and the lack of supporting tools for the analysis of smart contracts makes it very challenging to get insights into this eco-environment, where code gets executed through transactions performing value transfer of a crypto-currency. We address this problem and report on the use of unsupervised clustering techniques and a seed set of verified contracts, in this work we propose a framework to group together similar contracts within the Ethereum network using only the contracts publicly available compiled code. We report qualitative and quantitative results on a dataset and provide the dataset and project code to the research community. / Link to conference webpage: http://icccn.org/icccn17/workshop/

Formkrav i svensk avtalsrätt innebär bl.a. att vissa avtal måste tecknas i skriftlig form och att de ska undertecknas på papper. I och med digitaliseringen har dock elektroniska medel för ingående av avtal blivit mer och mer av en norm. Smart Contracts är avtal som med tekniska medel syftar till automatisera parternas avtalsprestationer och därmed göra det säkrare för parter att ingå avtal. Detta arbete syftar därmed till att utvärdera huruvida användandet av avtal som ingås via den tekniska företeelsen Smart Contracts kan ersätta användandet av formalavtal.

In the banking industry today there are processes in need of digitalisation to meet the digital needs of the customers. An area which is a candidate for digitalization is core banking which stands for Centralized Online Realtime Exchange and includes processes such as bank loans. By implementing the blockchain technology and smart contracts to core banking processes they can become digital and meet needs such as efficiency and transparency. The purposes of this master thesis are to examine the attitude Swedish banks have towards the blockchain technology, find out what core banking processes that could benefit from an implementation of a smart contract, and create an implementation model of a specific core banking process as a smart contract. By examining these topics a holistic perspective of how the blockchain technology can create value for the banks and customers can be reached to create a proof of concept model of a core banking process with the blockchain technology and smart contracts. The purposes are fulfilled by a literature study, interviews with representatives from Swedish banks, legal experts and requirements specialists and a model consisting of flowcharts, requirements,specifications, stakeholders and models in the blockchain platform Corda. Generally the banks have a positive attitude towards the blockchain technology but there are regulations that hinder the development process. Promissory notes was the process chosen to be implemented as a smart contract since itscharacteristics are fulfilled by the blockchain technology and according to thebanks this process would create the most value. According to a evaluation by the requirement experts at the employer Applicon the implementation model is suitable as a proof of concept and a good base for future prototyping.

The purpose of this Master's thesis is to explore blockchain technology and smart contracts as a way of building privacy-sensitive applications. The main focus is on a medication plan containing prescriptions, built on a blockchain system of smart contracts. This is an example use case, but the results can be transferred to other ones where sensitive data is being shared and a proof of validity or authentication is needed. First the problem is presented, why medication plans are in need of digitalisation and why blockchain technology is a fitting technology for implementing such an application. Then blockchain technology is explained, since it is a very new and relatively unfamiliar IT construct. Thereafter, a design is proposed for solving the problem. A system of smart contracts was built to prove how such an application can be built, and suggested guidelines for how a blockchain system should be designed to fulfil the requirements that were defined. Finally, a discussion is held regarding the applicability of different blockchain designs to the problem of privacy-handling applications. / Syftet med detta examensarbete är att utforska blockkedje teknologi och s.k. smarta kontrakt för att bygga applikationer där känslig information hanteras. Huvudsakligen ligger fokus på att utveckla en struktur baserad på blockkedje teknologi och smarta kontrakt för en medikationsplan. Detta är ett typ-exempel för att visa hur en sådan applikation kan byggas, men resultaten kan överföras till andra områden där känslig data delas mellan parter, eller där ett bevis för korrekthet krävs. Först presenteras problemet, varför medikationsplaner behöver digitaliseras och varför blockkedje teknologi är väl anpassat för att implementera en sådan applikation. Sedan förklaras blockkedje teknologi något djupare i detalj, eftersom det är ett relativt nytt koncept. Därefter föreslås en design för att lösa problemet.  Ett system av smarta kontrakt är byggt för att visa hur en medikationsplan kan byggas, och riktlinjer ges för hur ett blockkedje system bör se ut för att stödja systemet av smarta kontrakt. Till slut hålls en kortare diskussion om hur olika blockkedje-designer kan användas för att appliceras på problemet med känslig information. / <p>Presentation held externally at Technical University Munich on the 29-5-2017 10.50.</p>

Blockchain technology has become increasing popular with the advent of cryptocurrencies like Bitcoin. However, the technology lends itself to greater opportunities due to its inherent properties such as security and decentralization, and the possibility to transact without the need for intermediaries. Real estate is a massive industry which could greatly benefit from the use of blockchain technology. The current processes for purchasing property involve multiple third parties, all of whom charge a fee and delay the transaction process. Furthermore, once a property is purchased, the ownership records are insecurely recorded in centralized databases. These records are subject to loss, damage, or corruption due to negligence or fraudulent activity. This thesis investigates if blockchain smart contracts could be a feasible solution to these problems. The investigation consisted of a literature study to identify the potential benefits and limitations of smart contracts for property transactions. Based on the findings, a prototype was then developed to facilitate a key part of the property transaction process. The results demonstrated that blockchain smart contracts could address several crucial issues faced by the real estate industry, however, more work would need to be done before they could be commercially implemented on a large scale.

No description available.

The aim of this thesis is to create a concept of semi-centralized cryptocurrency that supports external interoperability. It is assumed that semi-centralized cryptocurrency is the future of cryptocurrencies in the banking sector, because even at the cost of partial centralization, the concept brings the benefits of a decentralized ledger. Since the simultaneous deployment of their own cryptocurrencies by various central authorities, such as central bank, it is necessary to establish a communication protocol for interbank transactions. The work is thus focused on extending the existing Aquareum solution with an interoperability protocol.

abstract: Blockchain technology enables peer-to-peer transactions through the elimination of the need for a centralized entity governing consensus. Rather than having a centralized database, the data is distributed across multiple computers which enables crash fault tolerance as well as makes the system difficult to tamper with due to a distributed consensus algorithm. In this research, the potential of blockchain technology to manage energy transactions is examined. The energy production landscape is being reshaped by distributed energy resources (DERs): photo-voltaic panels, electric vehicles, smart appliances, and battery storage. Distributed energy sources such as microgrids, household solar installations, community solar installations, and plug-in hybrid vehicles enable energy consumers to act as providers of energy themselves, hence acting as 'prosumers' of energy. Blockchain Technology facilitates managing the transactions between involved prosumers using 'Smart Contracts' by tokenizing energy into assets. Better utilization of grid assets lowers costs and also presents the opportunity to buy energy at a reasonable price while staying connected with the utility company. This technology acts as a backbone for 2 models applicable to transactional energy marketplace viz. 'Real-Time Energy Marketplace' and 'Energy Futures'. In the first model, the prosumers are given a choice to bid for a price for energy within a stipulated period of time, while the Utility Company acts as an operating entity. In the second model, the marketplace is more liberal, where the utility company is not involved as an operator. The Utility company facilitates infrastructure and manages accounts for all users, but does not endorse or govern transactions related to energy bidding. These smart contracts are not time bounded and can be suspended by the utility during periods of network instability. / Dissertation/Thesis / Masters Thesis Computer Science 2019

Blockchain technology has gained significant interest during the previous years and, to some extent, is accredited as a universal solution to enabling online transactions between unknown parties without the need for a central authority. However, as we have yet to see widespread blockchain adoption in government or industrial settings, the question arises: What are the technical challenges hindering blockchain adoption? To this end, a systematic literature review is conducted on 29 academic papers researching software engineering challenges in blockchaintechnology. Initially, the papers are inductively analysed to elucidate and identify the challenges frequently discussed in academic literature. Furthermore, a theoretical framework is produced by drawing from the models mainly used in traditional software development, followed by deductive analysis to map out the software engineering activities related to the challenges. Twenty-four challenges are identified, with 12 relating to smart contracts, 11 to blockchain, and 1 to decentralised applications. The most frequently addressed software engineering activity is design, followed by testing.

Background: Blockchain technology may seem like a complex system, but it is simply a decentralized database designed to remove the need for third-party organisation in data management. Blockchain is being researched for uses in the various industry out of which healthcare is one. Healthcare industry suffers from various issues such as imperfect data, a broken medical history that is split across various healthcare institutions, and so on. Blockchain might be the approach it needs to optimize it to a greater level of functioning. Objectives: The objectives of this report are to understand whether the decentralization feature along with other features of blockchain technology can be advantageous to the healthcare industry and also to summarize the previous implementation for the use cases of the technology in the domain. Methods: The method used is a literature survey. We perform a study selection process in four steps. After each step, the number of publications is reduced as unwanted publications are omitted using search strings, inclusion and exclusion criteria. We even conducted a study quality assessment which helps us analyse the quality offindings from the final set of selected papers in answering the research questions. Results: We have summarized the findings from the 36 selected papers from the study selection process according to the research questions. Conclusions: Blockchain technology provides data security, once any data is registered on the blockchain it cannot be altered or manipulated. It eliminates the need for a third party to verify the transactions on the chain. As blockchain is a budding new technology with very little age under its belt, there needs to more research on the topic before this can be applied over a large scale of systems that are operating in critical areas such as healthcare. Even though implementing blockchain for the use cases such as Electronic Medical Records (EMRs), research trials and so on, it can not be done immediately as the exposure of this technology to the common public and healthcare individuals is very limited.