Multi-chain bridges

Official bridge

Opside has a cross-chain bridge that supports asset interoperability between BTC, ETH, and other public chains to the Opside chain. This bridge uses chainsafe’s solution and is run by the trusted Opside official team. Deposit events on one chain are detected by a set of trusted off-chain relays, which wait for a final determination, submit the event to another chain, and vote on the submission to reach acceptance to trigger the appropriate handler.

We will evaluate the security, decentralization, and asset richness of the chains and choose which public chains to use as Opside’s layer 1. In the future, we will hand over the choice to the community through DAO. The community can vote to add more decentralized public chains and corresponding assets to the asset layer.

Liquidity bridge

At the same time, Opside supports a faster and cheaper decentralized liquidity bridge to achieve asset interoperability in more chains. The liquidity bridge consists of permissionless nodes that reach consensus on cross-chain messages through MPC. The liquidity pool brings faster speed and supports more public chains and their on-chain assets.

In addition, the liquidity bridge also connects all three layers of Opside, supporting direct token transfers between any two layers. For example, you can transfer tokens from layer-1 Ethereum to a layer-3 rollup using the liquidity bridge. This will reduce the steps and waiting time of cross-chain transfers, improving user experience.

Further: ZK-Bridge

Opside establishes connections with various public chains of the asset layer through the trustless ZK-Bridge. Compared with other bridge schemes, the ZK-Rollup scheme involves more ZK-proof systems. In the cross-chain operation, it is necessary to generate ZK Proofs to ensure the correctness of the execution process in addition to a general “execution.” The deposit and withdrawal operations of ZK-Bridge are “solidified” as a circuit, and the circuit logic is completely exposed. Corresponding to each circuit, there is a unique verification key. Verification keys are used at the asset layer to verify state proofs. The verified state proves that it conforms to the logic of the solidified circuit. In this cross-chain method, the submission is always correct, users do not have to worry about fraud, and there is no freezing period for withdrawing funds.

In addition to the cross-chain of assets, ZK-Bridge will also support more general cross-chain contract calls in the future, which means that DeFi applications on one chain can be called directly from another chain. Opside has defined a cross-channel protocol to handle contract calls between chains. Cross-chain contract calls will support all blockchains that have smart contracts.