Author: Michael Johnson

Ethereum is often described as a platform for self-enforcing smart contracts. While this is certainly true, this article argues that, especially when more complex systems are involved, it is rather a court with smart lawyers and a judge that is not so smart, or more formally, a judge with restricted computational resources. We will see later how this view can be leveraged to write very efficient smart contract systems, to the extent that cross-chain token transfers or computations like checking proof of work can be implemented at almost no cost. The Court Analogy First of all, you probably know that…

Update: We’ve released version 1.3.5 including networking hotfix for homestead 1.3.4.  Development of Ethereum started in December 2013 when two developers and a college dropout researcher decided to put their heads together and develop this amazing piece of technology. We were later joined by many like-minded individuals. Our first Proof of Concept (PoC) came on February 1, 2014. By the time we started our crowdsale on July 23, we were up to PoC 5 with a protocol that was almost finished, and had achieved compatibility between multiple clients. The team was psyched when we got our first million and our second…

After an additional two months of work after the release of the first python proof of concept release of Serenity, I am pleased to announce that Serenity PoC2 is now available. Although the release continues to be far from a testnet-ready client, much less a production-ready one, PoC2 brings with it a number of important improvements. First and foremost, the goal of PoC2 was to implement the complete protocol, including the basic corner cases (slashing bets and deposits), so as to make sure that we have a grasp of every detail of the protocol and see it in action even…

Ethereum’s present reliance on Proof of Work (PoW) mining is not ideal, and while we continue to work with gusto towards a Proof of Stake solution (PoS), we have to live with PoW as gracefully as possible (at least until the eventual switch!). Meanwhile, in the interest of overall network health, mining decentralization and diversity is a clear imperative: Though there are some instances of open source Ethereum pool mining software available, the uptake has been low, and there appears to be a large efficiency gap between proprietary and available open source pool software. We propose to change that. As…

Consensys and Microsoft have announced that the Ethereum contract programming language Solidity will be available in Microsoft’s Visual Studio integrated development environment. ConsenSys and Microsoft collaborated on this integration to enable developers to rapidly build smart contract-based applications for the public Ethereum blockchain, as well as private and consortium blockchain deployments based on Ethereum. This integration is being revealed at //Build, Microsoft’s annual developer conference, in San Francisco on March 30th; Vitalik Buterin, Consensys CEO Joseph Lubin and Consensys Enterprise director Andrew Keys will be present. Vitalik, Andrew and Microsoft CEO Satya Nadella at the //Build pre-conference reception The integration…

The Ethereum Foundation has announced that it will be working with the New York-based banking consortium R3CEV on creating a new blockchain-based cryptocurrency, Lizardcoin, which aims to showcase the benefits of blockchain technology as well as the consortium’s ability to bring the technology to institutional clients and the regulation-loving masses by supplementing it with a healthy dose of centralized control. Lizardcoin aims to be a direct competitor to Bitcoin as a store-of-value, beating out Bitcoin’s 21 million fixed supply cap with a first-in-its-class deflationary model, starting with a maximum supply of 20.9 million and then further reducing the supply by…

[Last update: July 5, 2016] The Ethereum Foundation and Wanxiang Blockchain Labs are excited to jointly announce the International Blockchain Week in Shanghai, which will take place at Hyatt on the Bund, September 19–24, 2016. Both Ethereum’s Devcon and Wanxiang Blockchain Labs’ Global Blockchain Summit were sold out last year with great interest and anticipation for this year’s events. Now, people who wish to attend both events can do so in the same week. The combined event features a unique three-segment format that allows people to attend any combination of days that best addresses their needs. Two new features include…

After almost three months into the “reboot” of the C++ team, I would like to give an update about the team itself, what we did and what we plan to do. Team update The so-called C++ team currently consists of Paweł Bylica (@chfast), Greg Colvin (@gcolvin), Liana Husikyan (@LianaHus), Dimitry Khokhlov (@winsvega), Yann Levreau (@yann300), Bob Summerwill (@bobsummerwill), me (@chriseth) and (kindly “donated” by Eris Industries) RJ (@VoR0220). Paweł is the original author of the llvm-based EVM-to-native just-in-time compiler, re-joined in April and will continue improving the JIT. Greg joined in February and already achieved substantial speedups for the C++ implementation…

Special thanks to Tim Swanson for reviewing, and for further discussions on the arguments in his original paper on settlement finality. Recently one of the major disputes in ongoing debate between public blockchain and permissioned blockchain proponents is the issue of settlement finality. One of the simple properties that a centralized system at least appears to have is a notion of “finality”: once an operation is completed, that operation is completed for good, and there is no way that the system can ever “go back” and revert that operation. Decentralized systems, depending on the specific nature of their design, may…

Affected configurations: All Go client versions  Likelihood: Very low Severity: High Details: A bug in Geth (and potentially other clients) may suffer from a DoS attack and allows remote attackers to stall synchronisation process almost indefinitely by supplying a valid, lighter chain. More information will be given out a later time including the report that was submitted through the bug bounty program. Effects on expected chain reorganisation depth: None Proposed temporary workaround: None Remedial action taken by Ethereum: Provision of hotfixes as below: If you’re using Mist: download the updated binary from the release page If using the PPA: sudo apt-get update then sudo apt-get upgrade If using brew: brew update then brew…