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La blockchain expliquée aux développeurs web, partie 1: la théorie. The Blockchain Explained to Web Developers, Part 1: The Theory. The blockchain is the new hot technology.

The Blockchain Explained to Web Developers, Part 1: The Theory

If you haven’t heard about it, you probably know Bitcoin. Well, the blockchain is the underlying technology that powers Bitcoin. Experts say the blockchain will cause a revolution similar to what Internet provoked. But what is it really, and how can it be used to build apps today? This post is the first in a series of three, explaining the blockchain phenomenon to web developers. To begin, let’s try to understand what blockchains really are. What Is A Blockchain, Take One Although the blockchain was created to support Bitcoin, the blockchain concept can be defined regardless of the Bitcoin ecosystem. The Blockchain Explained to Web Developers, Part 2: In Practice. Is the blockchain a revolution?

The Blockchain Explained to Web Developers, Part 2: In Practice

The technology that powers Bitcoin sure has the potential to disrupt the entire Internet, as we explained in a previous post. But how can you, a developer, use the blockchain to build applications? Are the tools easy to use, despite the complexity of the underlying concepts? How good is the developer experience? We wanted to find out, and there is no better tutorial than developing an app from scratch. Application Concept The blockchain shines when it replaces intermediaries. Since the famous Million Dollar Homepage experiment, innovating in the field of paid ads can’t make you rich anymore. Instead, we chose to build a tool that allows to display ads for free - a Zero Dollar Homepage.

User Workflow In concrete terms, whenever we merge a Pull Request (PR) on one of marmelab’s open-source repositories, a GitHub bot comments on the PR, and invites the PR author to publish their ad on the ad platform admin panel. Architecture. La blockchain expliquée aux développeurs web, 3ème partie : la vérité sur la blockchain. Après avoir exploré de manière théorique la blockchain, et après avoir utilisé la blockchain pour de vrai, nous avons maintenant une meilleure compréhension de ses forces et de ses faiblesses.

La blockchain expliquée aux développeurs web, 3ème partie : la vérité sur la blockchain

Surprise : nos conclusions sont très différentes de ce que vous pourrez lire ailleurs sur le web. Peut-être est-ce parce que nous ne relayons pas aveuglément la fascination ambiante, engendrée par l’impressionnante valorisation du BitCoin et des autres crypto-monnaies. The Blockchain Explained to Web Developers, Part 3: The Truth. After exploring the blockchain theory and using it for real, we now have a better understanding of its strengths and weaknesses.

The Blockchain Explained to Web Developers, Part 3: The Truth

Surprisingly, most of our conclusions are very different from what you will read in the blogosphere. Maybe it’s because we don’t blindly relay the fascination caused by the huge valuations of BitCoin and others. Maybe it’s because the hard truth about the blockchain is that it’s not ready yet. Read on to understand our take on the blockchain, based on strong evidence. The Technology Is Not Mature Enough As explained in detail in the previous post in this series, developing Decentralized Apps over a blockchain is a pain. It’s not that the Ethereum developers and community are bad ; they’re amazing, and they’re pouring a lot of time and expertise into their tools. Consensus (computer science) A fundamental problem in distributed computing is to achieve overall system reliability in the presence of a number of faulty processes.

Consensus (computer science)

This often requires processes to agree on some data value that is needed during computation. Examples of applications of consensus include whether to commit a transaction to a database, agreeing on the identity of a leader, state machine replication, and atomic broadcasts. The consensus problem requires agreement among a number of processes for a single data value. Some of the processes may fail or be unreliable in other ways, so consensus protocols must be fault tolerant. The processes must somehow put forth their candidate values, communicate with one another, and agree on a single consensus value. Preuve de travail.

Un article de Wikipédia, l'encyclopédie libre.

Preuve de travail

Un système de validation par preuve de travail (en anglais proof-of-work ou PoW) (ou protocole, ou la fonction) est difficile à produire car il est coûteux en temps et en énergie. C'est une mesure économique et sécuritaire pour dissuader, sur un réseau informatique, des attaques par déni de service et autres abus de service tels que le spam en requérant de la puissance de calcul et de traitement par ordinateur au demandeur de service. Le concept a d'abord été présenté par Cynthia Dwork et Moni Naor dans un article de 1993[1]. Le terme « preuve de travail » ou PoW a été formalisé dans un document de 1999 par Markus Jakobsson et Ari Juels[2].

Ethereum Project. Hyper Ledger Foundation. Monax. Getting Started. Eris is the ecosystem application platform built by Monax.

Getting Started

There are four steps need to get moving with Eris: Install the platform.Roll the blockchain base for your ecosystem application.Deploy your ecosystem application using smart contract templates and a simple, web-based user interface.Integrate your ecosystem application with a web server or other microservices. Dependencies: eris has 2 dependencies: Docker and Docker Machine. Docker is a run anywhere container solution which makes development, deployment, testing, and running of ecosystem applications a breeze and Docker Machine allows you to run Docker on remote machines.

For Linux, Docker Machine dependency is optional but recommended. Currently we consider the most workable setup to be (what our tests consider authoritative) with these operating system and dependencies’ versions: Host OS = UBUNTU:16.04Docker = 1.11.2Docker Machine = 0.8.1 We are working steadily toward making eris available for a wide variety of host environments. Explainers.