Rainbow Bridge

The Rainbow Bridge is the official bridge interface for transferring digital assets between the Ethereum, NEAR, and Aurora blockchains. It can be used between any one of these blockchains. The Rainbow Bridge was created by Aurora Labs, who also developed the EVM-compatible Aurora blockchain, which is built on the NEAR blockchain.

The Rainbow Bridge is a protocol that is currently responsible for connecting the three blockchains and can be used to transfer assets between any of the three supported networks. Additionally, it is the first trustless and permissionless bridge that connects the Ethereum, NEAR, and Aurora blockchains.

It is common for blockchain bridges to require their users to trust someone outside of the blockchains they wish to transfer assets between. In Rainbow Bridge, this problem has been solved, and when assets are transferred between two of these three chains, only the validators maintain security.

Anyone with a cryptocurrency wallet can access the Rainbow Bridge. If you wish to move assets between the Ethereum and Aurora blockchains, simply connect your MetaMask wallet. For NEAR blockchain transfers, you'll need a NEAR wallet. The Rainbow Bridge allows to bridge all ERC-20 tokens:

Depending on the direction chosen, asset bridging might involve one or two transactions. Transfers to the NEAR and Aurora blockchains require only one transaction and can take up to ten minutes. A transfer to the Ethereum blockchain requires two transactions and can take up to 16 hours, according to the platform documentation.

Here is an step-by-step example of how Rainbow Bridge works:

1. Using the Rainbow Bridge UI, I will transfer 100 USDC from NEAR to Ethereum blockchain
2. In response to my confirmation of the first of two transactions in my MetaMask wallet, Rainbow Bridge will transfer and lock 100 USDC in smart contracts. As of that moment, these USDC are no longer circulating on the NEAR blockchain
3. In accordance with the data from my transaction, Rainbow Bridge calculates a cryptographic confirmation that I have indeed locked the 100 USDC
4. The approval will enable me to proceed to the next step, namely, requesting smart contracts to create new 100 USDC on the Ethereum network
5. In requesting my 100 USDC, I am actually submitting my cryptographic confirmation that the 100 USDC has been locked
6. As a result, further cryptographic calculations are performed, and if the proofs match, 100 USDC will be created on the Ethereum blockchain and delivered to my cryptocurrency wallet

In the cryptocurrency world, Rainbow Bridge is one of the few bridges that are still resistant to hacker attacks. Hackers have already attempted to steal funds from it twice in 2022. Both of them were stopped by the automated mechanism Watchdog.

The important thing to keep in mind is that blockchain bridges are a common target for thieves since they contain all the supported assets circulating on other chains. Thus, never underestimate the importance of cybersecurity. This is because even a single incident, such as a bug in the code and a subsequent hack on the platform, can ruin the future of the entire project. This may also result in the loss of your investment. As a result of such an incident, users will be less motivated to invest their money and time in digital assets and Web 3.0. Be prepared to accept a certain level of risk and diversify your investments.

Rainbow Bridge is a well-known trustless & permissionless bridge that connects three popular blockchains – Ethereum, NEAR, and  Aurora. Developers have designed it so that there is no need to rely on anything other than the security of the chains themselves. The Rainbow Bridge protocol is designed to be completely decentralized, and to be able to adapt to any future protocol changes.

The Aurora Labs team behind Rainbow Bridge is currently working on automating the finalization of transfers. Thus, once a transfer is requested from the NEAR blockchain to the Ethereum blockchain, you will not need to perform a second confirmation transaction.