LNCS.

Smart contracts are computer programs that are executed by a network of mutually distrusting agents, without the need of an external trusted authority. Smart contracts handle and transfer assets of considerable value (in the form of crypto-currency like Bitcoin). Hence, it is crucial that their implementation is bug-free. We identify the utility (or expected payoff) of interacting with such smart contracts as the basic and canonical quantitative property for such contracts. We present a framework for such quantitative analysis of smart contracts. Such a formal framework poses new and novel research challenges in programming languages, as it requires modeling of game-theoretic aspects to analyze incentives for deviation from honest behavior and modeling utilities which are not specified as standard temporal properties such as safety and termination. While game-theoretic incentives have been analyzed in the security community, their analysis has been restricted to the very special case of stateless games. However, to analyze smart contracts, stateful analysis is required as it must account for the different program states of the protocol. Our main contributions are as follows: we present (i)~a simplified programming language for smart contracts; (ii)~an automatic translation of the programs to state-based games; (iii)~an abstraction-refinement approach to solve such games; and (iv)~experimental results on real-world-inspired smart contracts

Automated labeling of unknown contracts in Ethereum

yesSmart 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

Automated labeling of unknown contracts in Ethereum

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

Evolução da Tecnologia Smart Contracts pela Perspectiva dos Indicadores de Patentes

This paper deals with a quest for precedence and quantitative analysis on the evolution of the smart contracts theme, using patent filing as the main technological indicator. For the data collection the Questel Orbit®, Lens and Patent Inspiration platforms were used, applying as input the keywords "smart contract" or "smart contracts" for the searches in the titles and in the claims. Macro and Meso analyzes were carried out to identify the quantitative indicators of patents related to smart contracts. The investigations were carried out until April 2019 and brought the quantity of 1,452 patent inventions by Questel Orbit®, a result of 1,935 patent deposits by Lens and 660 patent application deposits. In all the platforms, there was a predominance of deposits made by the private sector (Companies) and the area of greatest relevance, as regards the technological domain of smarts contracts is the management model, representing 49% of patents verified.Este artigo trata de busca de anterioridade e análise quantitativa sobre a evolução do tema smart contracts, usando o depósito de patentes como principal indicador tecnológico. Para o levantamento dos dados utilizaram-se as plataformas Questel Orbit®, Lens e Patent Inspiration, aplicando como entrada as palavras-chaves “smart contract” ou “smart contracts” para as buscas nos títulos e nas reivindicações. Foram realizadas análises Macro e Meso, com o objetivo de identificar os indicadores quantitativos das patentes relacionadas aos smart contracts. As investigações foram realizadas até abril de 2019 e trouxeram o quantitativo de 968 invenções de patente pelo Questel Orbit®, um resultado de 1.935 depósitos de patentes pelo Lens e 660 depósitos pelo Patent Inspiration. Em todas as plataformas, houve uma predominância de depósitos realizados pelo setor privado (Empresas) e a área de maior relevância, quanto ao domínio tecnológico dos smarts contracts é o modelo de gestão, representando 49% das patentes verificadas

PSYCHOLOGICAL CONTRACT IN IMPROVING HUMAN RESOURCES STRATEGY WITH ORGANIZATIONAL CULTURE AS A MEDIATOR VARIABLE

The minimum criteria regarding the qualifications and competencies of lecturers in conducting education require psychological contracts, organizational culture and the strategy of Human Resources (HR) that are used as the basis for work relationships. The main objective of this research is to examine psychological contracts in improving HR strategies with organizational culture as a mediator variable. The method used in this research is kind of descriptive with a quantitative approach and use explanatory surveys. The research target was lecturers at several universities in Jambi Province. The data collection method used is by providing a structured questionnaire aimed at the sample respondents. The analysis tool used in this study is Partial Least Square (PLS) and the software used is smart-PLS. The research hypothesis provides strong support towards the view of psychological contracts has a positive and significant influence in improving HR strategies, psychological contracts have a positive and significant influence in improving HR strategies through organizational culture as a mediator variable

An empirical analysis of smart contracts: platforms, applications, and design patterns

Smart contracts are computer programs that can be consistently executed by a network of mutually distrusting nodes, without the arbitration of a trusted authority. Because of their resilience to tampering, smart contracts are appealing in many scenarios, especially in those which require transfers of money to respect certain agreed rules (like in financial services and in games). Over the last few years many platforms for smart contracts have been proposed, and some of them have been actually implemented and used. We study how the notion of smart contract is interpreted in some of these platforms. Focussing on the two most widespread ones, Bitcoin and Ethereum, we quantify the usage of smart contracts in relation to their application domain. We also analyse the most common programming patterns in Ethereum, where the source code of smart contracts is available.Comment: WTSC 201