Arbitrum Decentralization Update

Hey Arbinauts! Arbitrum Autumn has been going strong and as we crest into November we wanted to share some progress we’ve made towards decentralization.

When it comes to rollups, decentralization is an especially complex issue. Arbitrum is in beta today, but it’s important to reiterate that it is designed to derive its security from Ethereum, which we chose to help scale because we believe in the power and security that Ethereum’s decentralization brings.

Following that, as we continue to build out scaling solutions for Ethereum, decentralization is always front and center in our minds. That being said, there are multiple components of rollup protocols that require different types of work to distribute control including the sequencer, validators, and the admin or owners of the protocol contracts themselves. This complexity and separation means that properly decentralizing takes a large amount of time and coordination — in the interest of transparency we have an important update to share around our progress.

Expanded Validation on Arbitrum One

The update we want to share today is around validation. Validator nodes secure the Arbitrum chain, by posting assertions to the state of the chain, and challenging any fraudulent assertions made by other validators. Currently validation is permissioned, and on the path towards permissionless validation we’re excited to announce an expanded validator set. The broadened group of organizations securing the chain now include:

This list represents a variety of organizations and different communities so that many users can have comfort in a diverse set of validators securing the chain. We’re excited to have a broadened set of validators live on Arbitrum One, and look forward to continuing to share more around our plans for validation soon, including some exciting validator protocol updates and fully permissionless validation.

Pardon the nerd-snipe here, but a large part of what helped more validators get up and running easily is a major improvement we made to our block validation engine. In early September as part of our regular Nitro release cadence, we shipped a change that reduced performance costs for validator nodes by more than 90%. This heavily reduced the compute costs associated with running validator nodes by making the act of block validation incredibly performant.

This might seem like an otherwise normal step-change in a technology stack built by a team focused on constant iteration, but it’s actually a crucial upgrade necessary to enabling decentralization in the long term. Allowing more people to cheaply and easily operate validator nodes that secure rollup chains is a core tenet of mass participation and sustainable decentralization.

Looking Ahead

Decentralization is a long process, and while we’re super excited about today’s update, we’re even more excited to keep making progress towards further decentralization. Stay tuned across our channels, including our blog, twitter, discord, and telegram to be the first to know about upcoming developments. As always, we’re hiring, and if you want to be a part of the team that’s building out the future of decentralized scaling solutions please visit our careers page.



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