EIP-8025 -- Networking¶

This document contains the networking specifications for EIP-8025.

Note: This specification is built upon Fulu and imports proof types from proof-engine.md.

Table of contents¶

Table of contents
Constants
Execution
Helpers
Modified compute_fork_version
MetaData
The gossip domain: gossipsub
Topics and messages
- Global topics
- execution_proof
The Req/Resp domain
Messages
- ExecutionProofsByRoot
- GetMetaData v4
The discovery domain: discv5
ENR structure
- Execution proof awareness

Constants¶

Execution¶

Note: The execution values are not definitive.

Name	Value
`MAX_EXECUTION_PROOFS_PER_PAYLOAD`	`uint64(4)`

Helpers¶

Modified `compute_fork_version`¶

def compute_fork_version(epoch: Epoch) -> Version:
    """
    Return the fork version at the given ``epoch``.
    """
    if epoch >= EIP8025_FORK_EPOCH:
        return EIP8025_FORK_VERSION
    if epoch >= FULU_FORK_EPOCH:
        return FULU_FORK_VERSION
    if epoch >= ELECTRA_FORK_EPOCH:
        return ELECTRA_FORK_VERSION
    if epoch >= DENEB_FORK_EPOCH:
        return DENEB_FORK_VERSION
    if epoch >= CAPELLA_FORK_EPOCH:
        return CAPELLA_FORK_VERSION
    if epoch >= BELLATRIX_FORK_EPOCH:
        return BELLATRIX_FORK_VERSION
    if epoch >= ALTAIR_FORK_EPOCH:
        return ALTAIR_FORK_VERSION
    return GENESIS_FORK_VERSION

MetaData¶

The MetaData stored locally by clients is updated with an additional field to communicate execution proof awareness.

(
  seq_number: uint64
  attnets: Bitvector[ATTESTATION_SUBNET_COUNT]
  syncnets: Bitvector[SYNC_COMMITTEE_SUBNET_COUNT]
  custody_group_count: uint64  # cgc
  execution_proof_aware: bool  # eproof
)

Where

seq_number, attnets, syncnets, and custody_group_count have the same meaning defined in the previous documents.
execution_proof_aware indicates whether the node is aware of optional execution proofs. A value of True signals that the node understands execution proof gossip topics and can participate in execution proof propagation.

The gossip domain: gossipsub¶

Topics and messages¶

Global topics¶

`execution_proof`¶

This topic is used to propagate SignedExecutionProof messages.

The following validations MUST pass before forwarding the signed_execution_proof on the network, assuming the alias proof = signed_execution_proof.message:

[IGNORE] The proof's corresponding new payload request (identified by proof.public_input.new_payload_request_root) has been seen (via gossip or non-gossip sources) (a client MAY queue proofs for processing once the new payload request is retrieved).
[IGNORE] No valid proof has already been received for the tuple (proof.public_input.new_payload_request_root, proof.proof_type) -- i.e. no valid proof for proof.proof_type from any prover has been received.
[IGNORE] The proof is the first proof received for the tuple (proof.public_input.new_payload_request_root, proof.proof_type, signed_execution_proof.validator_index) -- i.e. the first valid or invalid proof for proof.proof_type from signed_execution_proof.validator_index.
[REJECT] The validator with index signed_execution_proof.validator_index is an active validator -- i.e. is_active_validator(state.validators[signed_execution_proof.validator_index], get_current_epoch(state)) returns True.
[REJECT] signed_execution_proof.signature is valid with respect to the validator's public key.
[REJECT] proof.proof_data is non-empty.
[REJECT] proof.proof_data is not larger than MAX_PROOF_SIZE.
[REJECT] All of the conditions within process_execution_proof pass validation.
[IGNORE] No valid proof has already been received for the tuple (proof.public_input.new_payload_request_root, proof.proof_type) -- i.e. no valid proof for proof.proof_type from any prover has been received.

The Req/Resp domain¶

Messages¶

ExecutionProofsByRoot¶

Protocol ID: /eth2/beacon_chain/req/execution_proofs_by_root/1/

The <context-bytes> field is calculated as context = compute_fork_digest(fork_version, genesis_validators_root).

Request Content:

1
2
3

(
  block_root: Root
)

Response Content:

1
2
3

(
  List[SignedExecutionProof, MAX_EXECUTION_PROOFS_PER_PAYLOAD]
)

Requests execution proofs for the given block_root. The response MUST contain all available proofs for the requested beacon block, up to MAX_EXECUTION_PROOFS_PER_PAYLOAD.

The following validations MUST pass:

[REJECT] The block_root is a 32-byte value.

The response MUST contain:

All available execution proofs for the requested block_root.
The response MUST NOT contain more than MAX_EXECUTION_PROOFS_PER_PAYLOAD proofs.

GetMetaData v4¶

Protocol ID: /eth2/beacon_chain/req/metadata/4/

No Request Content.