Hyperbridge (Nexus)

Hyperbridge is an interoperability coprocessor that has been designed with full node level security. By leveraging Polkadot as a consensus layer, we obtain high crypto-economic security, equivalent to about $5 billion at the time of writing. This ensures that hyperbridge is resistant to governance attacks that would’ve otherwise successfully compromised the protocol if it had to bootstrap its own validator set.

Hyperbridge inherits cheap consensus proofs through BEEFY, which attests to the validity of all parachain state transitions secured by the network. Because of this, we can shard the work of validating consensus, state proof and state transition re-execution across multiple so-called parachain cores. This allows us to aggregate the cross-chain messages from multiple connected blockchains which are verified on multiple parachain cores into a single zk consensus & state proof that can be verified cheaply on any chain.

This cost will be cheap enough to compete with non-consensus proof based bridges which simply verify MPC signatures onchain for attestation. It is critical to note that the reason this kind of interoperability coprocessor hasn’t been attempted before is because it is an architecture that is uniquely enabled by Polkadot. All of this culminates in what is undoubtedly the holy grail of interoperability: a single proof that aggregates multiple sub-proofs to facilitate the most secure and scalable cross-chain message passing.