This will greatly save time and costs for the existing setup, and can shorten the withdrawal time from the usual 7 days to just 1 hour. This is a key step for BOB in achieving Rollup Phase 1 and Phase 2 on L2beat.
On July 25, BOB (Build on Bitcoin) announced a partnership with the zero-knowledge proof infrastructure RISCZero, becoming the first Rollup project in the industry to use zero-knowledge proofs as fraud proofs through the integration of the hybrid architecture framework Kailua launched by RISC Zero. This will greatly save time and costs for the existing setup, and can shorten the withdrawal time from the usual 7 days to just 1 hour. This is a key step for BOB in achieving Rollup Phase 1 and Phase 2 on L2beat.
It is reported that Kailua is an OP stack extension built by RISC Zero using its verifiable computing layer Boundless network, which is a hybrid architecture that can upgrade Optimistic Rollup to Hybrid ZK Rollup (i.e., Hybrid Rollup). It combines the advantages of Optimistic Rollups and ZK Rollup, aiming to achieve efficient blockchain settlement and dispute resolution. It quickly processes transactions by default using Optimistic Rollups and enables ZK proofs when disputes arise or quick settlement is needed, thus attempting to balance high throughput, low cost, and high security. In simple terms, it integrates the capabilities of ZK Rollup advantages into the existing Optimistic Rollup.
The most important feature is that it can shorten the settlement period from the original 7-day challenge period to as little as 1 hour, and there is no need to worry about the ongoing generation costs of ZK proofs for Optimistic Rollup networks integrated with Kailua, as its implementation is on-demand.
BOB is the first chain to use zero-knowledge proofs (ZK). Compared to the slow withdrawal speed and expensive anti-fraud mechanisms of Optimistic Rollup, as well as the high operating costs of ZK Rollup, this new approach combines the advantages of both.
BOB perfectly combines efficiency (lower cost of submitting proposals compared to effective Rollup) and security (ability to prove the correctness of blocks in the event of fraud). Additionally, ZK proofs are much cheaper than the on-chain binary games on current Optimism or Ink platforms (less than $100, while the latter is about $1 million).
Three major advantages:
Anyone can challenge BOB sequencer's proposals with a margin as low as 0.5 ETH, without needing hundreds of ETH like non-zero-knowledge fraud proofs.
In the event of a challenge, the settlement of fraud proofs on Ethereum can be completed with just one transaction, allowing for finalization within minutes, while the non-zero-knowledge version requires hours or days and multiple transactions.
In the long run, BOB's withdrawal time can be significantly shortened, as the on-chain fraud resolution is fast and cost-effective. The initial expected withdrawal time is 4 days, and once the system stabilizes, it can be shortened to a few hours.
How it works:
Kailua introduces its self-developed new error-proof game design, providing top-notch security for Rollup transaction ordering.
BOB will use zero-knowledge proofs (ZK) for fraud proofs, rather than multiple transactions in the Optimism binary game.
Zero-knowledge proofs allow BOB to streamline the error-proof mechanism into a single transaction on Ethereum, rather than multiple transactions in the binary game.
Specific process:
For each checkpoint, the BOB sequencer (run by Conduit) will propose a new canonical chain for a specific height.
Anyone can use the Kailua binary file to propose another proposal, disputing the canonical chain. Proposing requires depositing a margin in ETH on Layer 1. The initial setting is 0.5 ETH, making it easy for anyone to challenge and significantly lowering the barrier for permissionless verification.
When there are conflicting proposals at the same height, the challenger or verifier (run by Conduit) will generate a zero-knowledge proof (using the Boundless algorithm) to resolve the issue with the canonical chain. Since BOB's construction depends on the order of transaction encoding on Layer 1, only one valid chain can exist. The margin of the incorrect proposer or challenger will be forfeited.
Alexei Zamyatin, co-founder of BOB and founding member of the BitVM Alliance, stated: "With the launch of a fully functional proof system, BOB L2 will have complete Ethereum security. This means BOB will still be in Phase 0 of the L2 layer, while most other L2 layers will move to other categories on L2Beat. The Rollup of Phase 1 only depends on the launch of the security council, which will be announced in the near future. The Rollup of Phase 2 only requires opening the proposal process to anyone."
The RISC Zero team believes that Kailua will upgrade Optimistic Rollup to use zero-knowledge proofs (ZK Fault Proofs) powered by RISC Zero zkVM. Currently, the market's choice for Rollup solutions is either Optimistic Rollup or ZK Rollup. Due to low costs and high throughput, Optimistic Rollup dominates the current market, but the 7-day challenge window delays finality and limits interoperability. ZK Rollup can provide fast finality, but generating ZK proofs for each block incurs significant additional costs, with high-throughput Rollup costs potentially reaching millions of dollars or more.
Now a third option has been launched on BOB, which is the solution supported by RISC Zero's Kailua architecture, combining the advantages of both methods: Optimistic ZK Rollup has the low operating costs of the Optimistic Rollup system and the fast finality of ZK Rollup.
免责声明：本文章仅代表作者个人观点，不代表本平台的立场和观点。本文章仅供信息分享，不构成对任何人的任何投资建议。用户与作者之间的任何争议，与本平台无关。如网页中刊载的文章或图片涉及侵权，请提供相关的权利证明和身份证明发送邮件到support@aicoin.com，本平台相关工作人员将会进行核查。
