Block structure & serialization

A zkopru block is submitted to the layer1 in a serialized form. Then, the checksum of the proposal becomes the proposal ID and is used for the challenge system.

Block structure

The zkopru block includes a header and a body.

Block details

Edit diagram here

Header

The first 340 bytes of the data should be the block header. The block header contains the following data:

Property	type
Proposer's address	address
Parent block hash	bytes32
Fee	uint256
Latest UTXO tree's root	uint256
Latest UTXO tree's leaf index	uint256
Nullifier tree's root	bytes32
Latest withdrawal tree's root	uint256
Latest withdrawal tree's leaf index	uint256
Transactions' root	bytes32
Deposits' root	bytes32
Migrations' root	bytes32

Body

A block body consists of transactions, mass deposits, and mass migrations. Moreover, the block header should contain correct information from the body. If the header does not have the correct value, the proposer will get slashed through the challenge system.

Transactions

Tx serialization

Mass deposits

Mass migrations