# Validation Cloud

### **Purpose**

Off-chain relayers in the validation cloud facilitate cross-chain communication by relaying messages from the source chain to the destination chain. They ensure seamless and reliable execution of cross-chain transactions within the VIA Labs ecosystem by picking up messages. 

NOTE: Developers building cross-chain contracts do NOT need to interface with the relayers / validation system. This is fully abstracted. See [HERE](https://developer.vialabs.io/general/package) for how to implement cross-chain contracts.

### **Functionality**

* **Execution Handling**: Triggers the `messageProcess()` on the destination contract, ensuring correct operation execution.
* **Gas Reimbursement**: An on-chain component pays initial gas fees for transactions. Destination contracts reimburse for these fees. More details are available in the[ Fees section](https://docs.vialabs.io/via-omnichain-network/fees) of the documentation.

For more infromation regarding validation or security, see [here](https://docs.vialabs.io/security/network-validator-intro).