CrossCurve Consensus Bridge

Overview

CrossCurve Consensus Bridge (CCB) is a cross-chain communication protocol that enables reliable data and asset transfers between networks without relying on centralized intermediaries.

The system is built on a consensus mechanism among independent cross-chain messaging services, ensuring the authenticity of cross-chain messages received on the destination network.

The goal of CCB is to provide developers with a secure way to connect their dApps, DeFi protocols, DAOs, and Infrastructure Services to a multi-network ecosystem using a standardized API and a minimal set of dependencies.

Architecture

Basic cross-chain schema

The fundamental model of cross-chain interaction has been used in various forms for quite some time.

In blockchain A, a contract calls a bridge contract function to send data to blockchain B. The bridge contract emits an event, which is picked up by its off-chain service. This service then creates a transaction containing the necessary data for the corresponding bridge contract on blockchain B. Upon receiving the transaction, the bridge contract verifies its validity and then invokes the target contract function, passing along the data received from blockchain A.

One of the core challenges lies in the fact that the bridge service operates outside the blockchain environment and therefore cannot be verified on-chain. Different bridge protocols address this issue in different ways.

CrossCurve Consensus Bridge, however, introduces a more comprehensive approach. It is not meant to replace existing protocols - instead, it integrates and leverages their mechanisms, creating a unified and verifiable cross-chain communication layer.

Consensus Bridge schema

The sender initiates a message in the source network by calling the CrossCurve Gatekeeper contract.
Depending on the destination chain, the Gatekeeper prepares and executes parallel message dispatches through multiple supported protocols. One of these protocols transmits the full message payload, while the others send verification proofs to confirm message authenticity.
Each protocol, following its standard cross-chain messaging process, independently delivers its data to the CrossCurve Receiver contract in the destination network.
The Receiver collects the received message instances and emits events as they arrive.
The external service CrossCurve Pusher monitors these events. Once the original message and a sufficient number of verification confirmations are detected, it submits an execution transaction to the CrossCurve Receiver contract.
Upon receiving the transaction from CrossCurve Pusher, the Receiver verifies the existence of the original message and all required confirmations from other protocols.
If validation is successful, the verified message is then delivered to its designated recipient.

Advantages

Security

CrossCurve Consensus Bridge provides a truly secure mechanism for cross-chain messaging.

Its minimal configuration requires three sovereign cross-chain protocols.

Even in this base setup, an attacker would need to gain simultaneous control over at least two out of the three protocols to compromise a message — making unauthorized interference practically infeasible.

Censorship Resistance

Decentralization is one of the most effective defenses against censorship.

However, in many cross-chain systems, services are often built on specific infrastructure stacks, which introduces potential points of control and censorship.

CrossCurve Consensus Bridge eliminates this issue by leveraging sovereign protocols that operate independently from one another.

For an adversary to block or alter message delivery through the bridge, they would need to control more than 50% of the protocols participating in the message channel (in the minimal setup, that means controlling two out of three).

Resilience

The consensus of independent protocols ensures not only security but also fault tolerance in message transmission. Even in its minimal configuration, if one of the three protocols becomes temporarily unavailable, the remaining two are sufficient to keep the CrossCurve Consensus Bridge fully operational.

In the rare event of a deadlock — when one or more bridges within the consensus experience prolonged downtime, potentially locking assets that relied on the consensus bridge — the situation remains recoverable. The CrossCurve DAO can replace the affected protocols in the consensus bridge of the impacted chain by approving a dedicated governance proposal.

Governance Protection

The CrossCurve Consensus Bridge is engineered for maximum security through the use of consensus among independent bridge protocols for data transmission.

Yet even the most secure systems can face potential vulnerabilities. The most common vector of attack targets governance mechanisms — an adversary might attempt to alter the composition of participating bridges, making it easier to compromise a single one.

In CrossCurve Consensus Bridge, such a scenario is structurally impossible.

Bridge configuration across all chain pairs is managed exclusively by the CrossCurve DAO. Any modification requires explicit community approval. The voting process lasts 7 days, and even after a proposal passes, the new configuration takes effect only after 24 hours, providing an additional safeguard and ensuring transparent governance.

This underlines the critical role of the CrossCurve DAO in maintaining decentralization across cross-chain messaging.

We believe that greater decentralization and resilience can be achieved when ecosystem participants — those advocating for transparency, stability, and security — become active members of the CrossCurve DAO. Their participation strengthens governance integrity and makes malicious decisions significantly harder to pass.

Capabilities

Cross-Chain Messaging

This is the foundation for building advanced cross-chain applications.

Through the Consensus Bridge, dApps gain a reliable communication layer between their instances deployed across different blockchains - or with APIs of other applications operating in separate networks.

Cross-Chain Token Transfers

Cross-chain token transfer applications using any combination of lock/mint or burn/mint models can rely on the Consensus Bridge as a trustless verification layer.

It provides accurate and verifiable information about token locking, minting, unlocking, or burning events across different blockchains.

Foundation for SuperDVN

The Consensus Bridge integrates seamlessly into the LayerZero cross-chain verification system.

This is achieved through a wrapper module called SuperDVN, which externally behaves like a standard DVN but internally performs multi-protocol consensus verification for enhanced security and reliability.

Supported Protocols

Currently, the CrossCurve Consensus Bridge supports the following messaging protocols:

CrossCurve Oracle Network
Layer Zero
Axelar
Router Protocol

Integration and Connection

The integration with the Consensus Bridge is planned to be permissionless. However, the protocol is currently operating in an experimental mode. If you’d like to connect, please contact us [email protected]

To send a message to a recipient on another chain, you need to:

Prepare the calldata for the target contract function with the required parameters.
Call the sendData function on the CrossCurve Gatekeeper contract:

sendData(
        bytes calldata data,
        bytes32 to,
        uint64 chainIdTo,
        bytes[] memory currentOptions
    ) external nonReentrant returns(uint256 fee)