Resultados de búsqueda para Blockchain

El control y trazabilidad de muestras biológicas es un problema a re-solver en un gran número de ámbitos, pero en lo que se refiere a laboratorios de reproducción humana asistida, existen una serie de factores ambientales y del propio contexto de trabajo que hace que la práctica est+AOk expuesta a múltiples po-sibles incidentes. En este contexto, investigadores del departamento de Lengua-jes y Sistemas Informáticos de la Universidad de Sevilla, han colaborado en un proyecto de transferencia tecnológica con la empresa andaluza G7innovation dentro del marco del proyecto +IBw-TRABIS – TRAzabilidad de muestras BIológicaS de reproducción humana asistida+IB0, cofinanciado por el Centro para el Desarrollo Tecnológico e Industrial (CDTI). TRABIS es una solución tecnológica e innova-dora que permite la ejecución y la monitorización de procesos de reproducción humana asistida, de manera integrada con dispositivos físicos de laboratorio para mejorar el control, salvaguarda y trazabilidad de muestras biológicas de paciente. Para alcanzar este objetivo, se han utilizado tecnologías como blockchain y smart contracts. Además, para verificar y validar la solución tecnológica, se ha reali-zado el pilotaje de la solución en Inebir (clínica privada de Reproducción Asis-tida).

Blockchain provides an immutable distributed ledger for storing transactions. One of the challenges of blockchain is the particular processing of dynamic queries due to accumulating costs. Complex Event Processing (CEP) provides efficient and effective support for this in a way, however, that is difficult to integrate with blockchain. This paper addresses the research challenges of integrating blockchain with CEP. More specifically, we envision an effective development environment in which (i) event-driven smart contracts are modeled in a graphical way, which are, in turn, (ii) automatically transformed into complementary code that is deployed in both a CEP engine and a blockchain network, and then (iii) executed on off-chain CEP applications which, connected to different data sources and sinks, automatically invoke smart contracts when event pattern conditions are met. We follow a classic systems engineering approach for defining the concepts of our system, called CEPchain, which addresses the described requirements. CEPchain was evaluated using a real-world case study for vaccine delivery, which requires an unbroken cold chain. The results demonstrate that our approach can be applied without requiring experts on event processing and smart contract languages. Our contribution simplifies the design of integrated CEP and blockchain functionality by hiding implementation details and supporting efficient deployment.

Blockchain es una tecnología relativamente reciente que permite la confiabilidad, trazabilidad, inmutabilidad y transparencia de la información. Ha traído numerosos beneficios en aplicaciones de Internet de las cosas (IoT) como son, la creación de redes seguras, dispositivos interconectados de forma confiable o la supresión de la falsificación de dispositivos. Sin embargo, su proliferación también ha dado lugar a la aparición de nuevos ciberataques que se desconocían hasta el momento. Este artículo presenta un estudio de mapeo sistemático sobre los ciberataques producidos en soluciones que integran redes blockchain, permisionadas y no permisionadas, en entornos IoT. Los resultados demuestran que el uso de la tecnología blockchain proporciona seguridad, transparencia y trazabilidad evitando así la manipulación de los datos en entornos IoT. Además, se confirma que Ethereum es actualmente la plataforma más utilizada que implementa la tecnología blockchain.

Blockchain es una base de datos distribuida y segura que puede ser aplicada en todo tipo de transacciones. La tecnología blockchain está creciendo en popularidad dado que permite desarrollar aplicaciones cuya información es confiable, transparente, inmutable y trazable. Dadas las ventajas que la blockchain proporciona frente a otros sistemas tradicionales, en este artículo presentamos una aplicación descentralizada (DApp) para la gestión de votaciones a rector de universidad de forma privada, pero a su vez transparente e inmutable, pudiéndose verificar públicamente y en tiempo real los resultados de las elecciones. Esta DApp, capaz de interactuar con la red blockchain pública Ethereum, ha sido desarrollada utilizando el marco de trabajo Truffle y el software MetaMask. Los resultados demuestran que es una aplicación de gran utilidad para llevar a cabo la transformación digital de las elecciones a rector de universidad.

During the last years, blockchain and smart contracts are receiving substantial mainstream attention from academia and industry. Blockchain is a distributed database that can be seen as a ledger that records all transactions that have ever been executed. In this context, smart contracts are pieces of software used to facilitate, verify, and enforce the negotiation of a transaction on a blockchain platform. This study aims to (1) identify and categorise the state-of-the-art related to smart contract languages, in terms of the existing languages and their main features, and (2) identify new research opportunities. As a result of the review protocol, 4,119 papers were gathered, and 109 of them were selected for extraction. The contributions are twofold: (1) 101 different smart contract languages have been identified and classified according to a variety of criteria; (2) a discussion on the findings and their implications for future research have been outlined. At first, almost 36% of the studies have been collected from grey literature (GitHub, webpages, etc.), which proves the importance of the industry in this field. We have identified the current challenges to reveal several gaps and raise open problems within the field. The most interesting open problems include the need to improve the developer coding experience by providing tools to write smart contracts as human-readable as possible, and the need to deal with Oracles and trusted off-chain information and processes. We find out many smart contract languages and blockchain platforms, making the ecosystem rather chaotic. However, there is no common or standard language to specify smart contracts that are valid regardless of the blockchain platform. This multivocal mapping study provides a snapshot of the smart contract languages field that serves as a baseline and a tool for future work, e.g., future surveys or future literature reviews in which particular issues or aspects such as security and privacy might be studied in further detail. To do that, we provide a bundle with all the resources at http://www.idea.us.es/smart-contract-languages/.

First Bitcoin in 2008, and later Ethereum in 2014, held a powerful promise: online decentralized governance, without servers or central controllers, not just for finance applications like crypto-currencies but for any organization. The so called Decentralized Autonomous Organizations (DAOs) were expected to fulfill such a promise, enabling people to organize online relying on blockchain-based systems and smart contracts automatizing part of their governance. In 2016, three DAO software frameworks +IBQ-Aragon, Colony and DAOstack+IBQ emerged aiming to facilitate development and experimentation in this field. To which extent do they facilitate DAO development today? This paper performs an analytical comparison of these three frameworks, focusing on their current functionalities for building DAOs. We find Aragon to be the most complete in several aspects. In order to provide more details on the challenges on building DAOs with current frameworks, we present a case study using the Aragon framework. Through this case study, we have piloted DAO development using this framework, and thus we may highlight the benefits, limitations and problems that developers face when adopting it. Our findings show that, even if Aragon does provide superior capabilities to other frameworks, it is still highly challenging to build a DAO with the current tools. Today, problems include issues on software engineering, instability, localization, documentation, lack of formalization and standards, and interoperability. Complementarily, this paper aims to provide some guidance to those developers aiming to face the challenges in developing a DAO, and to those aiming to fix the major weak points that make DAOs the organizations of a still distant future.

A pesar del interés que despierta la tecnología blockchain y los contratos inteligentes, su complejidad supone un problema que ralentiza su adopción. Con la intención de contribuir a minimizar este problema, en la última edición de estas jornadas presentábamos una propuesta metodológica y tecnológica para el uso de modelos en el ámbito de los contratos inteligentes. El objetivo de este trabajo es presentar los primeros resultados de esa propuesta.