This PR reintroduces and further decouples blocks and blobs in EIP-4844, so as to improve network and processing performance. Block and blob processing, for the purpose of gossip validation, are independent: they can both be propagated and gossip-validated in parallel - the decoupled design allows 4 important optimizations (or, if you are so inclined, removes 4 unnecessary pessimizations): * Blocks and blobs travel on independent meshes allowing for better parallelization and utilization of high-bandwidth peers * Re-broadcasting after validation can start earlier allowing more efficient use of upload bandwidth - blocks for example can be rebroadcast to peers while blobs are still being downloaded * bandwidth-reduction techniques such as per-peer deduplication are more efficient because of the smaller message size * gossip verification happens independently for blocks and blobs, allowing better sharing / use of CPU and I/O resources in clients With growing block sizes and additional blob data to stream, the network streaming time becomes a dominant factor in propagation times - on a 100mbit line, streaming 1mb to 8 peers takes ~1s - this process is repeated for each hop in both incoming and outgoing directions. This design in particular sends each blob on a separate subnet, thus maximising the potential for parallelisation and providing a natural path for growing the number of blobs per block should the network be judged to be able to handle it. Changes compared to the current design include: * `BlobsSidecar` is split into individual `BlobSidecar` containers - each container is signed individually by the proposer * the signature is used during gossip validation but later dropped. * KZG commitment verification is moved out of the gossip pipeline and instead done before fork choice addition, when both block and sidecars have arrived * clients may verify individual blob commitments earlier * more generally and similar to block verification, gossip propagation is performed solely based on trivial consistency checks and proposer signature verification * by-root blob requests are done per-blob, so as to retain the ability to fill in blobs one-by-one assuming clients generally receive blobs from gossip * by-range blob requests are done per-block, so as to simplify historical sync * range and root requests are limited to `128` entries for both blocks and blobs - practically, the current higher limit of `1024` for blocks does not get used and keeping the limits consistent simplifies implementation - with the merge, block sizes have grown significantly and clients generally fetch smaller chunks.
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 |
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0 | Phase0 | 0 |
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1 | Altair | 74240 |
|
2 | Bellatrix ("The Merge") |
144896 |
In-development Specifications
Code Name or Topic | Specs | Notes |
---|---|---|
Capella (tentative) | ||
EIP4844 (tentative) | ||
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:
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.