Chromia cross-chain capabilities

The Chromia token bridge enables seamless transfer of assets between Ethereum Virtual Machine (EVM)-compatible chains and Chromia. This cross-chain infrastructure allows Chromia dapps to integrate with the broader Ethereum ecosystem, providing enhanced interoperability for both users and developers.

Ethereum Interoperability Framework (EIF)

At the core of Chromia's cross-chain capabilities lies the Ethereum Interoperability Framework (EIF). This framework serves as the foundational infrastructure for communication between Chromia and EVM chains through two main components.

The Rell module handles the essential operations of cross-chain message processing and token bridging. It maintains state synchronization between chains, ensuring data consistency across the network.

The EVM smart contracts component manages the secure locking and unlocking of tokens. It validates transactions and controls the token release mechanisms, providing a secure bridge between different blockchain environments.

Pegged bridge implementation

The H-Bridge represents Chromia's standard implementation of the EIF framework. It uses a straightforward yet secure approach to token management. When bridging tokens, the original assets are locked in EVM chain smart contracts while equivalent tokens are minted on Chromia, maintaining a strict 1:1 backing ratio.

Currently, the H-Bridge actively facilitates CHR token bridging between Chromia's Economy Chain and major networks like Ethereum Mainnet and Binance Smart Chain. Future plans include support for popular stablecoins such as USDT and USDC.

Security architecture

Security is paramount in the bridge's design. The system implements robust validation requirements, including consensus-based validation and a supermajority requirement of provider signatures. This multi-layer verification process ensures the integrity of all cross-chain operations.

For incoming transfers from EVM to Chromia, the network performs thorough validation using Chromia consensus rules. This includes pre-minting verification and state consistency checks before processing any token minting.

Outgoing transfers from Chromia to EVM chains undergo smart contract validation and provider signature verification. This process ensures secure token release and maintains the integrity of the bridging mechanism.

Developer integration

The bridge infrastructure simplifies cross-chain development for builders. Developers can utilize standard token bridging functionality without building custom solutions. The system provides ready-to-use integration tools while supporting custom cross-chain applications.

Getting started with EVM integration

To implement EVM interoperability in your dapp:

Bridge and token deployment

• Bridge overview: Understand the bridge architecture and how cross-chain transfers work
• Bridge deployment: Follow the complete bridge deployment guide to set up cross-chain asset transfers
• Token deployment: Learn to deploy ERC20 tokens and configure bridging
• Bridge registration: Register your bridge with the network
• Chain deployment: Deploy bridge chains for your specific use case

Client integration and development

• Bridge client: Implement bridging in your frontend using the bridge client
• Client examples: See practical examples of bridge client integration
• Frontend interaction: Learn to interact with bridge frontend
• Bridge leasing: Understand bridge leasing for production deployments

Cross-chain communication

• ICMF protocol: Implement Interchain Messaging Facility for cross-chain communication
• ICCF protocol: Use Interchain Confirmation Facility for cross-chain confirmations
• Mass exit functionality: Handle emergency scenarios with mass exit operations

Troubleshooting and advanced features

• Troubleshooting: Use the bridge troubleshooting guides for common issues
• Smart contracts: Reference the EIF documentation for advanced smart contract interactions
• EIF configuration: Configure EVM event receiver settings for governance applications

These resources provide comprehensive guidance for integrating Chromia dapps with the broader EVM ecosystem, from basic bridge setup to advanced cross-chain applications.

Next up

Next, we will explore Chromia's protocols to understand how to manage accounts, tokens, and cross-chain communication on the network.