FIP-0011 Source

TitleRemove reward auction from reporting consensus faults
AuthorJakub Sztandera
Discussions-Tohttps://github.com/filecoin-project/FIPs/issues/61
StatusFinal
TypeCore
CategoryCore
Created2020-01-05

Spec Sections

FIP-0011: Remove reward auction from reporting consensus faults

Simple Summary

Reward from reporting currently undergoes reverse auction (Dutch auction). This FIP proposes and specifies removal of this auction mechanism and makes the full reward available immediately.

Abstract

Misbehaving miners can produce block which influence Expected Consensus’ fairness. The incentive for reporting Consensus Faults is a reward. This reward is in range 0.005 and 0.25 of Block Reward (~4 FIL full reward) determined by Dutch auction. The duration of auction is 500 epoch. For full reward that period has to elapse since the consensus fault was produced. For 50% reward the reporter has to wait 412 epochs. This significantly delays reporting of consensus faults, which ideally should be reported as soon as possible. This mechanism is a remainder of an old system where miner was completely removed from Filecoin and the reporter was awarded percentage of that miner’s collateral.

Change Motivation

There are multiple motivating factors for this change: - the current system was intended for different reward kind (percentage of collateral) - the current system disincentives swift reporting of consensus faults which is essential for EC - the new system increases the overall income from reporting consensus faults, which can have the effect of increasing the number of parties reporting consensus faults

Specification

Reporter reward changes from 0.001 to 0.05 of Consensus Fault Penalty (5*BlockReward) to BlockReward / 4. Where BlockReward is reward that is to be awarded a single miner at this epoch. The resulting reward is the same amount as maximum reward from Dutch auction.

Design Rationale

This is minimal change with aim of removing the Dutch auction mechanism while preserving the final amount. It also significantly simplifies how the reporter reward is calculated and unties it from Consensus Fault Penalty.

Backwards Compatibility

It is backward incompatible change that will require all implementations to adapt. It should be deployed as synchronised network upgrade. The proposed mechanism is much simpler than one currently specified.

Test Cases

WIP All valid ReportConsensusFault messages should result in full BR / 4 reward.

Security Considerations

Dutch auction mechanism was introduced to prevent miners exiting Filecoin network extracting the percentage of collateral, by self-reporting consensus faults. At the time, the fact that secret (non-published) consensus faults are easy to create was not considered and Dutch auction is not effective defense against this.

Currently Dutch auction does not serve any security related purpose apart from delaying the reporting of consensus faults.

Incentive Considerations

This change increases incentives for prompt reporting of consensus faults instead of waiting 400-500 epochs.

Product Considerations

Does not influence Filecoin as a Product other than improving stability of the network.

Implementation

WIP

Copyright and related rights waived via CC0.

Citation

Please cite this document as:

Jakub Sztandera, "FIP-0011: Remove reward auction from reporting consensus faults," Filecoin Improvement Proposals, no. 0011, January 2020. [Online serial]. Available: https://fips.filecoin.io/fips/fip-0011.