f97538719b
As part of the discussions surrounding EIP-7594 (peerdas), it was highlighted that during sampling and/or data requests, the sampler does not have timing information for when a samplee will have data available. It is desireable to not introduce a deadline, since this artificially introduces latency for the typical scenario where data becomes available earlier than an agreed-upon deadline. Similarly, when a client issues a request for blocks, it does often not know what rate limiting policy of the serving end and must either pessimistically rate limit itself or run the risk of getting disconnected for spamming the server - outcomes which lead to unnecessarily slow syncing as well as testnet mess with peer scoring and disconnection issues. This PR solves both problems by: * removing the time-to-first-byte and response timeouts allowing requesters to optimistically queue requests - the timeouts have historically not been implemented fully in clients to this date * introducing a hard limit in the number of concurrent requests that a client may issue, per protocol * introducing a recommendation for rate limiting that allows optimal bandwidth usage without protocol changes or additional messaging roundtrips On the server side, an "open" request does not consume significant resources while it's resting, meaning that allowing the server to manage resource allocation by slowing down data serving is safe, as long as concurrency is adequately limited. On the client side, clients must be prepared to handle slow servers already and they can simply apply their existing strategy both to uncertainty and rate-limiting scenarios (how long before timeout, what to do in "slow peer" scenarios). Token / leaky buckets are a classic option for rate limiting with desireable properties both for the case when we're sending requests to many clients concurrently (getting good burst performance) and when the requestees are busy (by keeping long-term resource usage in check and fairly serving clients)
Ethereum Proof-of-Stake Consensus Specifications
To learn more about proof-of-stake and sharding, see the PoS documentation, sharding documentation and the research compendium.
This repository hosts the current Ethereum proof-of-stake specifications. Discussions about design rationale and proposed changes can be brought up and discussed as issues. Solidified, agreed-upon changes to the spec can be made through pull requests.
Specs
Core specifications for Ethereum proof-of-stake clients can be found in specs. These are divided into features. Features are researched and developed in parallel, and then consolidated into sequential upgrades when ready.
Stable Specifications
| Seq. | Code Name | Fork Epoch | Specs |
|---|---|---|---|
| 0 | Phase0 | 0 |
|
| 1 | Altair | 74240 |
|
| 2 | Bellatrix ("The Merge") |
144896 |
|
| 3 | Capella | 194048 |
|
| 4 | Deneb | 269568 |
In-development Specifications
| Code Name or Topic | Specs | Notes |
|---|---|---|
| Electra | ||
| Sharding (outdated) |
|
|
| Custody Game (outdated) |
|
Dependent on sharding |
| Data Availability Sampling (outdated) |
|
Accompanying documents can be found in specs and include:
Additional specifications for client implementers
Additional specifications and standards outside of requisite client functionality can be found in the following repos:
Design goals
The following are the broad design goals for the Ethereum proof-of-stake consensus specifications:
- to minimize complexity, even at the cost of some losses in efficiency
- to remain live through major network partitions and when very large portions of nodes go offline
- to select all components such that they are either quantum secure or can be easily swapped out for quantum secure counterparts when available
- to utilize crypto and design techniques that allow for a large participation of validators in total and per unit time
- to allow for a typical consumer laptop with
O(C)resources to process/validateO(1)shards (including any system level validation such as the beacon chain)
Useful external resources
For spec contributors
Documentation on the different components used during spec writing can be found here:
Online viewer of the latest release (latest master branch)
Consensus spec tests
Conformance tests built from the executable python spec are available in the Ethereum Proof-of-Stake Consensus Spec Tests repo. Compressed tarballs are available in releases.