[DRAFT] Eth1-Eth2 Communication Protocol

This document has been deprecated and superseded by https://notes.ethereum.org/@n0ble/rayonism-the-merge-spec

The Communication Protocol between eth2 and eth1 nodes sufficient for implementation of Executable Beacon Chain proposal.

Reference

• eth2_produceBlock
• eth2_insertBlock
• eth2_setHead
• eth2_finalizeBlock

Constants

Name	Value
LOGS_BLOOM_SIZE	256
MAX_TRANSACTIONS	2**32
MAX_PAYLOAD_SIZE	2**32
RECENT_BLOCK_ROOTS_SIZE	256

Structures

ExecutableData

class Transaction(Container):
    nonce: uint64
    gas_price: uint256
    gas: uint64
    to: bytes20
    value: uint256
    v: uint256
    r: uint256
    s: uint256
    input: ByteList[MAX_PAYLOAD_SIZE]    

class ExecutableData(Container):
    parent_hash: bytes32
    block_hash: bytes32
    coinbase: bytes20
    state_root: bytes32
    gas_limit: uint64
    gas_used: uint64
    receipt_root: bytes32
    logs_bloom: ByteVector[LOGS_BLOOM_SIZE]
    transactions: [Transaction, MAX_TRANSACTIONS]
    
    # for easier eth1-engine upgradability
    # will be removed later on
    difficulty: uint64

Eth1 Block

class BlockHeader:
    # = rpc_params.parent_hash / executable_data.parent_hash
    parent_hash: bytes32          
    uncles_hash: bytes32           # = EMPTY_LIST_HASH
    coinbase: bytes20              # = exec_data.coinbase
    state_root: bytes32            # = exec_data.state_root
    txs_root: bytes32              # = exec_data.txs_root
    receipts_root: bytes32         # = exec_data.receipts_root
    logs_bloom: bytes256           # = exec_data.logs_bloom
    difficulty: uint64             # = exec_data.difficulty
    timestamp: uint64              # = rpc_params.timestamp
    number: uint64                 # = exec_data.number
    gas_limit: uint64              # = exec_data.gas_limit
    gas_used: uint64               # = exec_data.gas_used
    mix_hash: bytes32              # = zero bytes
    extra_data: bytes32            # = rpc_params.randao_mix
    nonce: uint64                  # = 0

class Block:
    header: BlockHeader
    transactions: [Transaction]    # = exec_data.transactions
    uncles: []                     # = empty list

eth2_produceBlock

Creates a new executable data on top of given parent.

Parameters

1. parent_hash: Hash - parent eth1 block hash.
2. randao_mix: Root - randao mix.
3. slot: UInt64 - current slot.
4. timestamp: UInt64 - timestamp, computed with the formula genesis_time + slot * SECONDS_PER_SLOT.
5. recent_beacon_block_roots: SSZVector[Root, RECENT_BLOCK_ROOTS_SIZE].

Returns

1. executable_data: ExecutableData, SSZ encoded.

eth2_insertBlock

Inserts a block into a chain and returns a result.

Parameters

1. randao_mix: Root - randao mix.
2. slot: UInt64 - current slot.
3. timestamp: UInt64 - timestamp, computed with the formula genesis_time + slot * SECONDS_PER_SLOT.
4. recent_beacon_block_roots: SSZVector[Root, RECENT_BLOCK_ROOTS_SIZE].
5. executable_data: ExecutableData, SSZ encoded.

Returns

1. Object - the result of block processing:

• result: Boolean

eth2_setHead

Parameters

1. block_hash: Hash - the hash of the head of the application chain.

Returns

1. Object - the result of processing:

• result: Boolean

eth2_finalizeBlock

Parameters

1. block_hash: Hash - the hash of finalized eth1 block.

Returns

1. Object - the result of block processing:

• result: Boolean