What is a blockchain bridge?

Blockchain bridges allow interoperability between very different networks, such as between Bitcoin and Ethereum, and between parent chains and child chains operating under different consensus rules than parent chains, or between parent chains and parents. Allows interoperability between child chains that take over the security of the chain (eg rollups on Ethereum) 1 . Child chains are also known as side chains. This interoperability also allows the movement of tokens, data, and even Bridge Smart Contract Development Services between independent platforms, allowing users to:

• Deploy digital assets on one blockchain with dapp on another chain

• Execute transactions of tokens in chains that are difficult to scale without going through a bridge at high speed and low cost

• Run dapp on multiple platforms

• Some blockchain bridges are centralized, while others maintain decentralization, which is crucial to the security and openness of the DeFi protocol.

Locking and Publishing: The essence of distributed bridges

When migrating assets from one blockchain to another using a decentralized bridge, the assets to be migrated are not literally “transferred” or “sent”. In reality, it goes through a two-step process. First of all, use smart contracts on the blockchain that has the assets you want to migrate and lock or “freeze” those assets. If smart contracts are not supported, use other mechanisms 2 . Next, the same amount of new tokens will be issued on the receiving blockchain. When you want to get your first asset back, you can unlock the first asset by burning the issued token. This process makes it impossible to use assets in two chains at the same time, Cross chain bridge development no matter what method is used.

Let’s take Ren Protocol 3 as an example of a distributed blockchain bridge . Just as Ethereum networks are supported by thousands of nodes, Ren virtual machines (RenVMs) are also supported by large distributed networks made up of devices that form consensus. Because sensitive information is shared across multiple devices , users can lock their digital assets on a blockchain in the network by leveraging multi-party computing (MPC) to share encrypted signatures. , You can publish digital assets of the same value in other chains in a trust-free way.

In this way, users can “move” from one blockchain, which is (theoretically) any digital asset, to another blockchain without the assistance of a third party. RenVM currently supports BTC, BCH, ZEC and DOGE on Ethereum and Binance smart chains4 .

Side chain bridge

Unlike a bridge that connects two completely different blockchains, a sidechain bridge connects a parent chain and its childchain. Parent chains and child chains operate under different consensus rules, so these communications also require a bridge.

As an example of this, the developers of the popular blockchain game Axie Infinity have created a dedicated sidechain called Ronin that connects to Ethereum. This will allow Axie Infinity to grow on a larger scale than the Ethereum mainnet5 . Ronin users deposit ETH, ERC20 tokens and NFTs into smart contracts at Ronin’s Ethereum Bridge. Ronin’s validator will then receive the deposited asset and relay it to the sidechain .

Another example is the Ethereum — based sidechain xDai6 . In xDai as well as Ronin, validators different from the miners who maintain the main chain of Ethereum maintain security. Two bridges, called xDai Bridge and OmniBridge , serve as a bridge between xDai and the Ethereum mainnet, which makes it easy to transfer tokens .

Sidechain will also play an important role in scaling the network since Ethereum 2.0 through the use of rollups. Rollup is a method of combining transactions from multiple sidechains into one transaction and ensuring security in the mainchain

Benefits of blockchain bridges for DeFi

By improving interoperability on the blockchain, including interoperability between the mainchain and sidechain, users can access the benefits of each chain without sacrificing the benefits of the chain they are currently using. It is possible to. Bridges are expected to have the following impacts and use cases:

Cross-chain collateral : Build a cross chain bridge allow users to move from blockchains like Bitcoin, which are of great value but with few dapps, to blockchains like Ethereum, where the DeFi ecosystem is evolving and requires additional liquidity. Digital assets can be migrated.

Scalability: Bridges designed to handle large numbers of transactions allow developers and users to achieve greater scalability without abandoning the liquidity and network effects of the original chain. This is especially important as the network congestion issue on Ethereum continues as we wait for the full deployment of Ethereum 2.0 .

Efficiency Users can instantly pay and receive small amounts without paying high gas bills . This will improve your gaming and e-commerce experience.

Enjoy the benefits of all chains

Blockchain bridges allow users to access the benefits of different blockchain technologies without having to choose a platform. Not only does this ease the burden on Ethereum, the most popular DeFi network,Build a token bridge, but it also encourages innovation in other ecosystems without forcing the idea of winner-take-all.