Ethereum is a decentralized platform that runs smart contracts, applications that run exactly as programmed without possibility of downtime, censorship, fraud or third party interference. In this blog post I will take you through all the steps required in setting up a fully functioning private ethereum blockchain, inside your local network — which includes:
- Setting up a private blockchain with ethereum using geth.
- Setting up the MetaMask ethereum wallet to work with the private blockchain.
- Transfer funds between multiple accounts.
- Create, deploy and invoke a smart contract on the private blockchain using remix.
- Setting up ethereum block explorer over the private blockchain.
Kind of a big deal. You’d have to be a total square not to have heard about them. Me? I’ve got eight.
Often over-complicated, over-mysticised, over-singularised (I don’t even know what the right word for it is, but people say The Blockchain a lot). What are they? Join me for a rough tour from the ground up and I’ll try to make sure you leave here knowing the answer to one question:
What are people talking about when they talk about blockchains?
There’s a lot to cover, so it’s actually going to come in two parts. This, the first, will look at the data structures known as blockchains and their properties, along with any other bits and pieces you need to make sense of them.
The second part will apply what you’ve learnt to the practical and widespread applications of blockchains to power distributed ledgers, cryptocurrencies such as Bitcoin and Litecoin and smart-contract based chains like Etherium.
This guide is meant to serve as both an easy-to-understand introduction to the world of cryptocurrencies as well as an insightful view into the different projects competing for your investments and market dominance and a look at the underlying technology, history and trends.
For many years Bitcoin would occasionally appear in the media after it spiked in price. I didn’t think there was anything inherently useful about it. I thought it was a novelty, a ponzi scheme, hysteria. It was only after the most recent price spike in another cryptocurrency, Ethereum, that the crazy returns finally tempted me. What started out as a skeptical look into a get-rich-quick scheme led me down a rabbit hole and my mind was promptly blown at the potential of the technology. The hype surrounding it is nothing short of mania, but it’s not without merit. Cryptocurrencies will almost certainly revolutionize everything from insurance, logistics and the stock market to ownership and even create entire economies which don’t currently exist. You may feel skeptical when hearing something so optimistic but when banks, governments and research institutions start to take notice and want to work with these projects maybe it’s time we paid some attention.
Many of you reading may be likening the current craze with the dotcom bubble and I’m afraid I absolutely agree with you. The speculation surrounding cryptocurrencies and the ease of which the average person can invest has created an environment where an idea can raise hundreds of millions of dollars without even a proof of concept. This is part of the reason this guide was written, to steer you clear of these massively overvalued “pet.com” equivalents and towards the future Amazons and Googles.
Cryptographic hash functions like SHA-1 are a cryptographer’s swiss army knife. You’ll find that hashes play a role in browser security, managing code repositories, or even just detecting duplicate files in storage. Hash functions compress large amounts of data into a small message digest. As a cryptographic requirement for wide-spread use, finding two messages that lead to the same digest should be computationally infeasible. Over time however, this requirement can fail due to attacks on the mathematical underpinnings of hash functions or to increases in computational power.
Today, 10 years after of SHA-1 was first introduced, we are announcing the first practical technique for generating a collision. This represents the culmination of two years of research that sprung from a collaboration between the CWI Institute in Amsterdam and Google. We’ve summarized how we went about generating a collision below. As a proof of the attack, we are releasing two PDFs that have identical SHA-1 hashes but different content.
For the tech community, our findings emphasize the necessity of sunsetting SHA-1 usage. Google has advocated the deprecation of SHA-1 for many years, particularly when it comes to signing TLS certificates. As early as 2014, the Chrome team announced that they would gradually phase out using SHA-1. We hope our practical attack on SHA-1 will cement that the protocol should no longer be considered secure.
We hope that our practical attack against SHA-1 will finally convince the industry that it is urgent to move to safer alternatives such as SHA-256.
Curated list of blockchain and general cryptocurrency resources
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