Ethereum consensus client in Rust
414197b06d
## Proposed Changes Mitigate the fork choice attacks described in [_Three Attacks on Proof-of-Stake Ethereum_](https://arxiv.org/abs/2110.10086) by enabling proposer boost @ 70% on mainnet. Proposer boost has been running with stability on Prater for a few months now, and is safe to roll out gradually on mainnet. I'll argue that the financial impact of rolling out gradually is also minimal. Consider how a proposer-boosted validator handles two types of re-orgs: ## Ex ante re-org (from the paper) In the mitigated attack, a malicious proposer releases their block at slot `n + 1` late so that it re-orgs the block at the slot _after_ them (at slot `n + 2`). Non-boosting validators will follow this re-org and vote for block `n + 1` in slot `n + 2`. Boosted validators will vote for `n + 2`. If the boosting validators are outnumbered, there'll be a re-org to the malicious block from `n + 1` and validators applying the boost will have their slot `n + 2` attestations miss head (and target on an epoch boundary). Note that all the attesters from slot `n + 1` are doomed to lose their head vote rewards, but this is the same regardless of boosting. Therefore, Lighthouse nodes stand to miss slightly more head votes than other nodes if they are in the minority while applying the proposer boost. Once the proposer boost nodes gain a majority, this trend reverses. ## Ex post re-org (using the boost) The other type of re-org is an ex post re-org using the strategy described here: https://github.com/sigp/lighthouse/pull/2860. With this strategy, boosted nodes will follow the attempted re-org and again lose a head vote if the re-org is unsuccessful. Once boosting is widely adopted, the re-orgs will succeed and the non-boosting validators will lose out. I don't think there are (m)any validators applying this strategy, because it is irrational to attempt it before boosting is widely adopted. Therefore I think we can safely ignore this possibility. ## Risk Assessment From observing re-orgs on mainnet I don't think ex ante re-orgs are very common. I've observed around 1 per day for the last month on my node (see: https://gist.github.com/michaelsproul/3b2142fa8fe0ff767c16553f96959e8c), compared to 2.5 ex post re-orgs per day. Given one extra slot per day where attesting will cause a missed head vote, each individual validator has a 1/32 chance of being assigned to that slot. So we have an increase of 1/32 missed head votes per validator per day in expectation. Given that we currently see ~7 head vote misses per validator per day due to late/missing blocks (and re-orgs), this represents only a (1/32)/7 = 0.45% increase in missed head votes in expectation. I believe this is so small that we shouldn't worry about it. Particularly as getting proposer boost deployed is good for network health and may enable us to drive down the number of late blocks over time (which will decrease head vote misses). ## TL;DR Enable proposer boost now and release ASAP, as financial downside is a 0.45% increase in missed head votes until widespread adoption. |
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| account_manager | ||
| beacon_node | ||
| book | ||
| boot_node | ||
| common | ||
| consensus | ||
| crypto | ||
| database_manager | ||
| lcli | ||
| lighthouse | ||
| scripts | ||
| slasher | ||
| testing | ||
| validator_client | ||
| .dockerignore | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmodules | ||
| bors.toml | ||
| Cargo.lock | ||
| Cargo.toml | ||
| CONTRIBUTING.md | ||
| Cross.toml | ||
| Dockerfile | ||
| Dockerfile.cross | ||
| LICENSE | ||
| Makefile | ||
| README.md | ||
| SECURITY.md | ||
Lighthouse: Ethereum consensus client
An open-source Ethereum consensus client, written in Rust and maintained by Sigma Prime.
Overview
Lighthouse is:
- Ready for use on Ethereum consensus mainnet.
- Fully open-source, licensed under Apache 2.0.
- Security-focused. Fuzzing techniques have been continuously applied and several external security reviews have been performed.
- Built in Rust, a modern language providing unique safety guarantees and excellent performance (comparable to C++).
- Funded by various organisations, including Sigma Prime, the Ethereum Foundation, ConsenSys, the Decentralization Foundation and private individuals.
- Actively involved in the specification and security analysis of the Ethereum proof-of-stake consensus specification.
Staking Deposit Contract
The Lighthouse team acknowledges
0x00000000219ab540356cBB839Cbe05303d7705Fa
as the canonical staking deposit contract address.
Documentation
The Lighthouse Book contains information for users and developers.
The Lighthouse team maintains a blog at lighthouse.sigmaprime.io which contains periodical progress updates, roadmap insights and interesting findings.
Branches
Lighthouse maintains two permanent branches:
stable: Always points to the latest stable release.- This is ideal for most users.
unstable: Used for development, contains the latest PRs.- Developers should base their PRs on this branch.
Contributing
Lighthouse welcomes contributors.
If you are looking to contribute, please head to the Contributing section of the Lighthouse book.
Contact
The best place for discussion is the Lighthouse Discord server.
Sign up to the Lighthouse Development Updates mailing list for email notifications about releases, network status and other important information.
Encrypt sensitive messages using our PGP key.
Donations
Lighthouse is an open-source project and a public good. Funding public goods is hard and we're grateful for the donations we receive from the community via:
- Gitcoin Grants.
- Ethereum address:
0x25c4a76E7d118705e7Ea2e9b7d8C59930d8aCD3b(donation.sigmaprime.eth).