[Constitutional AIP] Activate Arbitrum BoLD + Infura Nova Validator Whitelist

Abstract

This constitutional AIP proposes upgrading both Arbitrum One and Arbitrum Nova to use a new dispute resolution protocol, called Arbitrum BoLD, and the addition of Infura to Arbitrum Nova’s validator whitelist. Specifically, this AIP combines the following two temperature check votes:

BoLD - permissionless validation for Arbitrum

This proposal requests the ArbitrumDAO to approve the upgrade of Arbitrum One and Arbitrum Nova to utilize Arbitrum BoLD: a new dispute resolution protocol that is designed to replace the currently deployed dispute resolution protocol. If this upgrade is approved, validators on Arbitrum One and Arbitrum Nova can use Arbitrum Nitro software to post assertions and to challenge invalid assertions. Note validation will be permissionless on Arbitrum One but remain permissioned on Arbitrum Nova (also elaborated on further down in this proposal). 

This upgrade will ensure that any single honest party can always successfully defend against malicious claims to an Arbitrum chain’s state. Arbitrum BoLD represents the next step on the journey to having the Arbitrum technology stack being recognized as a Stage 2 Ethereum rollup. 

The implementation of BoLD has been thoroughly tested and audited to ensure both its effectiveness and safety. Note that Orbit chains may choose to adopt Arbitrum BoLD as soon as the BoLD upgrade is generally available and formally supported, regardless of whether the ArbitrumDAO approves this proposal or not.

Whitelist Infura’s Nova Validator

This proposal requests that the ArbitrumDAO whitelist Infura’s Nova validator.

The addition of Infura to Arbitrum Nova’s validator whitelist will increase the number of active validators on Arbitrum Nova, enhancing the network’s overall security, stability, and reliability. Infura has a proven track record in running blockchain infrastructure and has already been participating on Arbitrum Nova’s Data Availability Committee (DAC), but was not previously whitelisted as a validator. 

Motivation

The ArbitrumDAO should consider approving this AIP because both the adoption of Arbitrum BoLD and the whitelisting of Infura’s Arbitrum Nova validator will enhance the network’s security, stability, and resiliency. Both of these proposed changes will benefit all Arbitrum users, Arbitrum node operators, dApps on Arbitrum, and Arbitrum bridges. 

Specifically, passing this governance proposal would mean that Arbitrum One and Arbitrum Nova will gain the following benefits:

• Permissionless validation for Arbitrum One - Today, the critical role of being a validator for Arbitrum One is currently restricted to a permissioned set of validators in order to prevent delay attacks on the current rollup protocol - a class of attacks where malicious actors can delay assertion confirmations if they, the malicious actors, are willing to sacrifice their stakes. However, since BoLD mitigates the risks of delay attacks using a different mechanism (i.e. by enforcing a fixed upper time bound on dispute resolution), reliance on a permissioned set of validators is no longer necessary. Therefore, passing this AIP and implementing BoLD to secure Arbitrum One would effectively enable permissionless validation, marking a key milestone for Arbitrum chains to be recognized as Stage 2 Rollups, a critical part of Arbitrum’s journey to full decentralization. Please see the dedicated section and recommendation for Arbitrum Nova below.
• Fixed delay time for assertion confirmation - The current dispute protocol for Arbitrum chains has a ~6.4 day challenge period, during which validators can dispute claims about the chain’s state. These claims about the chain’s state are called “assertions”. While assertions are confirmable after 1 challenge period, malicious actors can open many challenges to delay confirming these assertions in a type of attack known as a delay attack. BoLD guarantees that all assertions, if there is a dispute using the validating bridge contract, will be confirmed within a fixed time window of 2 challenge periods (~6.4 days each), 2 day grace period for the Security Council to intervene, and a small delta for computing challenges.
• Increased censorship resistance for Orbit L3s settling to Arbitrum One or Arbitrum Nova - As mentioned in the original Arbitrum BoLD Forum Post, the initial release of BoLD will come with a feature called ”Censorship Timeout” (originally called “Delay Buffer”). The Censorship Timeout feature provides stronger guarantees of censorship resistance for Arbitrum chains - especially those that settle to Arbitrum One and Nova - by introducing a programmatic way for the parent chain contracts to lower the force inclusion time window in cases where the L2 sequencer is offline or censoring. For Arbitrum One and Arbitrum Nova, it is proposed that this feature be enabled by default alongside BoLD’s upgrade. Please see the dedicated section on Censorship Timeout for more details.
• Preserves the current security primitives with a Safety-First approach - In the event of a dispute using BoLD, there is a 2 day "grace period" (also called the “challenge grace period”) that is applied to the winning assertion before it is confirmed. This time window allows time for the Security Council to intervene if there are any severe bugs in the BoLD contracts that would cause an invalid assertion to confirm.The duration of the grace period is configurable by the ArbitrumDAO and would initially be set to 2 days. 
• Improved network stability and reliability for Arbitrum Nova with the addition of a new validator to the whitelist - The addition of Infura to Arbitrum Nova’s validator whitelist will increase the number of active validators on Arbitrum Nova, enhancing the network’s overall security, stability, and reliability. Infura has a proven track record in running blockchain infrastructure and has already been participating on Arbitrum Nova’s Data Availability Committee (DAC), but was not previously whitelisted as a validator. 

Rationale

Enabling permissionless validation is a critical milestone on Arbitrum's journey toward full decentralization, while maintaining network resiliency. These milestones help ensure Arbitrum technology remains the industry-leading choice for Ethereum scaling solutions. BoLD directly benefits users through guaranteed withdrawal times and enhanced security, while allowing anyone to participate in network validation. Meanwhile, the addition of Infura’s validator to the Arbitrum Nova whitelist will increase the number of active validators on Arbitrum Nova, enhancing the network’s overall reliability.

Specifically, this AIP is:

• Ethereum-aligned: BoLD would strengthen Arbitrum One's connection to Ethereum by leveraging its security while making validation accessible to everyone - matching Ethereum's core value of openness. Similarly, the addition of Infura’s validator to the Arbitrum Nova whitelist would support Ethereum's commitment to decentralization by supporting a more diverse validator set.
• Sustainable: BoLD is meant to secure Arbitrum chains sustainably in the long-term, and there are already future investments and research expected following the initial launch to ensure BoLD and its security guarantees evolve alongside the Arbitrum protocol, technology, and community. Lastly, by leveraging Infura’s proven infrastructure, the proposal would help ensure long-term operational stability and network reliability for Arbitrum Nova.
• Secure: BoLD significantly enhances Arbitrum's and rollup chains' security by allowing more validators to monitor the network while maintaining Ethereum's robus

... please visit link below to view full proposal

https://tally.xyz/gov/arbitrum/proposal/101924107818180443784046677916233531742645798596604549673138282938475874935972