Omnic Crosschain Messaging Protocol

Omnic is a crosschain messaging protocol, powered by the Internet Computer's threshold ECDSA and outbound http call features, we can build programmability into the message passing process.

Currently support EVM compatible chains.

1. Architecture

Core components:

• Gateway contracts living on EVM chains:

  • receive crosschain message requests from application contracts on local chain, messages are organized into a merkle tree;
  • receive crosschain messages from external chains and notify recipient contracts on the local chain.

• Omnic proxy canister living on the IC:

  • verify messages from offchain relayer(using the merkle roots fetched by gateway canisters), forward crosschain messages:
    • if message destination is IC, proxy canister notify the recipient canister on IC
    • if message destination is another chain, proxy canister create and sign a tx to the Omnic gateway contract on the destination chain, gateway contract will then notify the recipient contract

• Omnic gateway canisters living on the IC:

  • each chain has a dedicated gateway canister, controlled by the Omnic proxy canister
  • responsible for periodically fetching message merkle roots from external chains, for later message verification use

• Omnic offchain relayer:

  • fetch crosschain messages from supported chains; fetch known merkle roots from Omnic proxy canister
  • generate a merkle proof for each message then send the proof along with the message to the proxy canister
  • Why offchain: Proof generation can be computational intense & fetch messages via http calls in canister is expensive. If cost is low, relayer can also be a canister onchain.

• Applications

  • Application canisters living on IC
  • Application contracts living on external EVM chains

2. TODOs

• Fix todos in code
• Add more chains
• Add examples
• ...

3. Deployment

Omnic test version is live on IC and 2 evm testnets:

Omnic proxy canister on IC mainnet: y3lks-laaaa-aaaam-aat7q-cai

Omnic gateway contract on EVM chains:

• Goerli: 0xc7D718dC3C9248c91813A98dCbFEC6CF57619520
• Mumbai: 0x2F711bEbA7a30242f4ba24544eA3869815c41413

4. Code

1. core: Omnic message passing protocol core implementation
2. examples: Example apps built on Omnic messaging protocol
3. omnic-bridge: A demo bridge app based on the Omnic messaging protocol
4. omnic-relayer: Omnic offchain relayer implementation

Note: This project is unaudited and still in very early experimental stage!