Ethereum System

Contains management functions to manage functions on Ethereum. For example, creating agents and channels.

Release

Polkadot SDK Stable 2412

lib.rs:

Governance API for controlling the Ethereum side of the bridge

Extrinsics

Agents

Agents are smart contracts on Ethereum that act as proxies for consensus systems on Polkadot networks.

• Call::create_agent: Create agent for a sibling parachain
• Call::transfer_native_from_agent: Withdraw ether from an agent

The create_agent extrinsic should be called via an XCM Transact instruction from the sibling parachain.

Channels

Each sibling parachain has its own dedicated messaging channel for sending and receiving messages. As a prerequisite to creating a channel, the sibling should have already created an agent using the create_agent extrinsic.

• Call::create_channel: Create channel for a sibling
• Call::update_channel: Update a channel for a sibling

Governance

Only Polkadot governance itself can call these extrinsics. Delivery fees are waived.

• Call::upgrade`: Upgrade the gateway contract
• Call::set_operating_mode: Update the operating mode of the gateway contract
• Call::force_update_channel: Allow root to update a channel for a sibling
• Call::force_transfer_native_from_agent: Allow root to withdraw ether from an agent

Typically, Polkadot governance will use the force_transfer_native_from_agent and force_update_channel and extrinsics to manage agents and channels for system parachains.

Polkadot-native tokens on Ethereum

Tokens deposited on AssetHub pallet can be bridged to Ethereum as wrapped ERC20 tokens. As a prerequisite, the token should be registered first.

• Call::register_token: Register a token location as a wrapped ERC20 contract on Ethereum.