This EIP removes the legacy deposit and Eth1 data fields from the BeaconBlockBody and BeaconState structures after EIP-6110 has been fully finalized. These fields become obsolete once all validators have transitioned to the new in-protocol deposit processing mechanism introduced in EIP-6110.
EIP-6110 introduced in-protocol deposit processing by moving validator deposits to the execution layer as part of the EIP-7685 request framework. This change eliminated the need for the consensus layer's proposer voting mechanism for deposits. However, during the transition period, both the legacy deposit mechanism (using deposits and eth1_data fields) and the new mechanism coexist to ensure smooth migration.
Once EIP-6110 has been fully finalized and the transition period is complete (when state.eth1_deposit_index == state.deposit_requests_start_index), the legacy deposit fields become permanently unused and can be safely removed. The Fulu fork removed legacy deposit processing and requires body.deposits to be empty. This EIP removes the remaining deposits and eth1_data block body fields, the Eth1 data voting machinery, and the unused BeaconState fields, providing several benefits:
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 and RFC 8174.
This EIP SHALL only be activated when both of the following conditions are met:
state.eth1_deposit_index == state.deposit_requests_start_indexThe BeaconBlockBody container is modified to remove the following fields:
Removed fields:
eth1_data: Eth1Datadeposits: ProgressiveList[Deposit]The removal is expressed by setting the corresponding active_fields bits of the ProgressiveContainer to 0, as specified in EIP-7688.
The updated BeaconBlockBody structure becomes:
class BeaconBlockBody(
ProgressiveContainer(active_fields=[1] + [0] + [1] * 4 + [0] + [1] * 6)
):
randao_reveal: BLSSignature
# Removed `eth1_data`
graffiti: Bytes32
proposer_slashings: ProgressiveList[ProposerSlashing]
attester_slashings: ProgressiveList[AttesterSlashing]
attestations: ProgressiveList[Attestation]
# Removed `deposits`
voluntary_exits: ProgressiveList[SignedVoluntaryExit]
sync_aggregate: SyncAggregate
bls_to_execution_changes: ProgressiveList[SignedBLSToExecutionChange]
signed_execution_payload_bid: SignedExecutionPayloadBid
payload_attestations: ProgressiveList[PayloadAttestation]
parent_execution_requests: ExecutionRequests
Block processing modifications:
process_eth1_data() call from process_blockassert len(body.deposits) == 0 check from process_operationsEpoch processing modifications:
process_eth1_data_reset() call from process_epochHonest validator modifications:
get_eth1_vote machinery; proposers no longer include an eth1_data vote in their blocksThe BeaconState container is modified to remove the following fields:
Removed fields:
eth1_data: Eth1Dataeth1_data_votes: List[Eth1Data, EPOCHS_PER_ETH1_VOTING_PERIOD * SLOTS_PER_EPOCH]eth1_deposit_index: uint64deposit_requests_start_index: uint64The removal is expressed by setting the corresponding active_fields bits of the ProgressiveContainer to 0.
The updated BeaconState structure becomes:
class BeaconState(
ProgressiveContainer(active_fields=[1] * 8 + [0] * 3 + [1] * 17 + [0] + [1] * 17)
):
genesis_time: uint64
genesis_validators_root: Root
slot: Slot
fork: Fork
latest_block_header: BeaconBlockHeader
block_roots: Vector[Root, SLOTS_PER_HISTORICAL_ROOT]
state_roots: Vector[Root, SLOTS_PER_HISTORICAL_ROOT]
historical_roots: List[Root, HISTORICAL_ROOTS_LIMIT]
# Removed `eth1_data`
# Removed `eth1_data_votes`
# Removed `eth1_deposit_index`
validators: ProgressiveList[Validator]
balances: ProgressiveList[Gwei]
randao_mixes: Vector[Bytes32, EPOCHS_PER_HISTORICAL_VECTOR]
slashings: Vector[Gwei, EPOCHS_PER_SLASHINGS_VECTOR]
previous_epoch_participation: ProgressiveList[ParticipationFlags]
current_epoch_participation: ProgressiveList[ParticipationFlags]
justification_bits: Bitvector[JUSTIFICATION_BITS_LENGTH]
previous_justified_checkpoint: Checkpoint
current_justified_checkpoint: Checkpoint
finalized_checkpoint: Checkpoint
inactivity_scores: ProgressiveList[uint64]
current_sync_committee: SyncCommittee
next_sync_committee: SyncCommittee
latest_block_hash: Hash32
next_withdrawal_index: WithdrawalIndex
next_withdrawal_validator_index: ValidatorIndex
historical_summaries: List[HistoricalSummary, HISTORICAL_ROOTS_LIMIT]
# Removed `deposit_requests_start_index`
deposit_balance_to_consume: Gwei
exit_balance_to_consume: Gwei
earliest_exit_epoch: Epoch
consolidation_balance_to_consume: Gwei
earliest_consolidation_epoch: Epoch
pending_deposits: ProgressiveList[PendingDeposit]
pending_partial_withdrawals: ProgressiveList[PendingPartialWithdrawal]
pending_consolidations: ProgressiveList[PendingConsolidation]
proposer_lookahead: Vector[ValidatorIndex, (MIN_SEED_LOOKAHEAD + 1) * SLOTS_PER_EPOCH]
builders: ProgressiveList[Builder]
next_withdrawal_builder_index: BuilderIndex
execution_payload_availability: Bitvector[SLOTS_PER_HISTORICAL_ROOT]
builder_pending_payments: Vector[BuilderPendingPayment, 2 * SLOTS_PER_EPOCH]
builder_pending_withdrawals: ProgressiveList[BuilderPendingWithdrawal]
latest_execution_payload_bid: ExecutionPayloadBid
payload_expected_withdrawals: ProgressiveList[Withdrawal]
ptc_window: Vector[Vector[ValidatorIndex, PTC_SIZE], (2 + MIN_SEED_LOOKAHEAD) * SLOTS_PER_EPOCH]
The fields are removed after EIP-6110 finalization to ensure:
Because BeaconBlockBody and BeaconState are ProgressiveContainers, the proposed changes do not affect the generalized indices of remaining fields. Merkle-proof verifiers of unrelated fields continue to work. Historical blocks and states retain their original schemas and remain verifiable.
The removal of legacy fields poses minimal security risk because:
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