Ethereum layer-2 solution Optimism has reached “Stage 1” decentralisation by integrating fault proofs into its smart contracts, as announced by its development team, OP Labs. This marks a significant milestone in line with goals set by Ethereum co-founder Vitalik Buterin.
At least four other OP Stack networks—Base, Metal, Mode, and Zora—will implement the fault proofs “soon.”
Users can now withdraw Ether and ERC-20 tokens on Optimism “without involvement from any trusted third parties,” OP Labs said in a post. In addition, if the team’s sequencer attempts invalid withdrawals, they can be “challenged and removed” by any user who submits a fault-proof showing that the withdrawal is invalid.
The sequencer can still block valid withdrawals or process invalid ones, because the fault proofs can be overridden by a six-of-eight vote from the Optimism Security Council. However, users now execute the default process for validating withdrawals instead of the Optimism team, and this process can only be overridden through an explicit vote of the Council.
This step towards “Stage 1” is seen as progress toward full decentralisation or “Stage 2.” At that stage, the Security Council can only intervene if a bug causes discrepancies among proving systems.
The fault-proof system, “Cannon,” was developed by multiple teams, including OP Labs, Base network, and Sunnyside Labs. The change was approved by Optimism’s Token House and Citizens’ House governance organisations.
Cannon is not the final fault-proof system for Optimism. Future plans include achieving “multi-proof nirvana,” where multiple proof systems will ensure only valid transactions are processed by the sequencer.
OP Labs assured that security is maintained with safeguards allowing the Security Council to act quickly if bugs are found, resetting and reproving all pending withdrawals if needed.
In an interview, Optimism founder Karl Floersch highlighted the network’s significant strides towards decentralisation despite challenges.
“[T]he reason why it’s so hard to build any proof system whatsoever is because it is the most security-critical code and requires unbelievable levels of assurance,” he stated. “We’re not at the Stage 2 end game, but we’re starting to see the pieces come together.”
Floersch anticipates the network’s move to Stage 2 would be “swift and decisive” now that Stage 1 is achieved, with multiple client implementations and ongoing development of various proof systems.
Ethereum layer-2 networks, or “rollups,” aim to reduce transaction fees by processing some data off-chain. However, they face criticism for centralised control, as seen in paused withdrawals or transaction censorship. The terms “Stage 1” and “Stage 2” refer to decentralisation milestones outlined by Vitalik Buterin, who advocates for a gradual shift towards full decentralisation.
