Challenge Initiation
Last updated
Last updated
Once a Validating Node (VN) detects a discrepancy, it initiates a challenge. For the challenge to proceed, the VN must provide clear proof to justify the challenge. This proof is essential to ensure that the challenge is valid and is not raised without substantial evidence.
If the discrepancy is related to incorrect sequencing, where the sequencer has processed orders in the wrong order, the VN must provide timestamps and data logs from both the off-chain sequencer and on-chain data.
Proof Required:
Order timestamps from the sequencer that show when each transaction was received.
A log of the actual order sequence processed by the sequencer.
Comparison of the timestamps to show the correct sequence of events (e.g., that Order B should have been processed before Order C, but the sequencer processed Order C first).
The corresponding on-chain (Submission B) records showing the mismatch, if relevant.
Example: The VN submits proof showing that:
Order B was received at 10:01 AM and Order C at 10:02 AM.
The sequencer, however, processed Order C first, even though it arrived later. This would be enough evidence for the challenge to pass to the next phase.
If the challenge is due to a mismatch between the off-chain order and its corresponding on-chain transaction, the VN must present proof comparing the two sets of data, showing the inconsistency between what was processed off-chain and what was posted on-chain.
Proof Required:
Off-chain (Submission A) transaction logs that include the details of the transaction as processed by the sequencer.
On-chain (Submission B) transaction data as posted on-chain, such as amounts, transaction IDs, and other relevant information.
A comparison of both off-chain and on-chain data to show the discrepancy (e.g., an on-chain order for 1 BTC is posted off-chain as 0.5 BTC).
Example:
A VN provides evidence showing that:
The off-chain record for Order A was to sell 0.5 BTC for 1 ETH.
The on-chain record for Order A shows 1 BTC for 1 ETH.
This mismatch between off-chain and on-chain data would serve as valid proof for the challenge.
When orders are posted directly on-chain through the Submission B method, these mismatches can be easily identified. Since Submission B directly records the order on the blockchain without going through the centralized sequencer, it provides a clear, immutable source of truth. VNs can compare the data from Submission B (the on-chain version) with the off-chain logs processed by the sequencer. Any discrepancies between the two would immediately stand out, making it straightforward for VNs to detect and challenge errors.
If the sequencer has excluded an order that should have been processed and posted on-chain, the VN must prove that the order was submitted but was not included on-chain.
Proof Required:
Proof of submission that the order was valid and was submitted directly on-chain (Submission B), along with the exact details (e.g., order details, submission time).
A check of the off-chain records proving that the order was never included or posted by the sequencer (Submission A).
Example: If Order A (sell 1 BTC for 1 ETH) was submitted directly on-chain and never processed by the sequencer, the VN provides logs showing the order was received directly on-chain but was not processed by the sequencer. This would serve as evidence of the exclusion.
