# CrossCurve SuperDVN
## Overview
**CrossCurve SuperDVN** is a verification module (**DVN**, **Decentralized Verification Network**) compatible with the **LayerZero** [**DVN** **standard**](https://medium.com/layerzero-official/layerzero-v2-explaining-dvns-02e08cce4e80). It leverages the **CrossCurve Consensus Bridge** as its internal mechanism for cross-chain message verification and transmission.
**SuperDVN** serves as a sovereign data verification layer for cross-chain applications, providing a decentralized, secure, and resilient environment for communication between blockchains.
## Architecture
**LayerZero** uses **DVNs** to achieve decentralized verification of cross-chain message transfers. However, ensuring robust security requires two or more independent **DVNs**.
For developers, **SuperDVN** appears as a single **DVN**, but internally it contains a consensus layer composed of multiple messaging protocols, combining their verification capabilities for enhanced reliability and trustlessness.
#### Message Flow:
* The **OApp** application sends a message on the source network to the **LayerZero** [**Endpoint contract**](https://docs.layerzero.network/v2/concepts/protocol/layerzero-endpoint).
* The **LayerZero protocol** processes the message in its standard way and forwards it for verification to the **CrossCurve DVN** contract.
* The **CrossCurve DVN** prepares and sends the verification data to the **CrossCurve Gatekeeper**.
* The **Gatekeeper** dispatches this data through multiple messaging protocols.
* Each protocol, following its standard cross-chain messaging procedure, independently delivers the data to the **CrossCurve Receiver** contract.
* The **Receiver** collects the incoming message instances and emits events upon receipt.
* 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** checks that the original message and all required protocol confirmations are present.
* If verification succeeds, the data is passed back to the **CrossCurve DVN**, which forwards the verification data to the **ReceiveLib contract** to complete the verification process and allow **LayerZero** to proceed with message delivery.
## Integration with LayerZero
**SuperDVN** is fully compliant with the **LayerZero** [**DVN Standard**](https://docs.layerzero.network/v2/concepts/modular-security/security-stack-dvns), which provides:
Ability to connect as a primary **DVN** for cross-chain messaging between networks using **LayerZero**.
Support for custom **DVN**, allowing **SuperDVN** to be used for specific applications.
Compatibility with the **LayerZero ecosystem** without the need to modify smart contracts.
## Supported Protocols
**SuperDVN** leverages **CrossCurve Consensus Bridge** to enhance verification security.
Currently, the **Consensus Bridge** supports the following messaging protocols:
* **CrossCurve Oracle Network**
* [**LayerZero**](https://layerzero.network/)
* [**Axelar**](https://www.axelar.network/)
* [**Router Protocol**](https://www.routerprotocol.com/)
## Connection and Integration
To integrate **SuperDVN** into an **OApp**, you need to configure the **ULN** as specified in the **LayerZero** [**documentation**](https://docs.layerzero.network/v2/developers/evm/configuration/dvn-executor-config).
Here is an example configuration for using a single **SuperDVN**:
**SuperDVN.address** — the address of the **SuperDVN contract** on the **OApp network** that sends the message.
```solidity
const ulnConfig = {
confirmations: 1,
requiredDVNCount: 1,
optionalDVNCount: 0,
optionalDVNThreshold: 0,
requiredDVNs: [SuperDVN.address],
optionalDVNs: []
};
const encodedUlnConfig = ethers.utils.defaultAbiCoder.encode(
["tuple(uint64 confirmations, uint8 requiredDVNCount, uint8 optionalDVNCount, uint8 optionalDVNThreshold, address[] requiredDVNs, address[] optionalDVNs)"],
[ulnConfig]
);
```
## Contracts
To configure the **OApp**, use the following contract addresses:
