deposit transactions on the layer-1 contract create a MassDeposit object, "Migration" type outputs of transactions can create a MassMigration that constructs a MassDeposit for its destination network.migrateTo function on the source network can be executed. The function moves the assets, including Ether, ERC20, and ERC721, while creating a MassDeposit object for the destination network.acceptMigration function. Also, it is recommended to allow migrations only from trusted networks.