When the first generation of blockchain, Bitcoin launched, it started as an independent, standalone network doing its own thing. Ethereum launched years later with the same structure - independent. After that, more and more blockchains sprung up as independent chains. However, with time, people began to see the need for these blockchains to communicate and interact with each other.

The first attempt at encouraging blockchain interoperability is what we know as “blockchain bridges” and they emerged before interoperability protocols were developed. This article aims to dive into blockchain bridges and how they work.

Firstly, let’s begin by explaining what a blockchain is

Blockchain

A blockchain is a distributed, decentralized ledger system that securely records transactions across a vast network of computers, referred to as nodes. Transactions are stored in blockchains and these blocks are connected, hence the name “blockchain”. Because of this structure's immutability and openness, it is more difficult for one party to alter the data.

Blockchain Bridges

Blockchain bridges are tools that make it easier for various blockchain networks to communicate with one another, enabling the easy transfer of assets and data between them.

As explained earlier, blockchains are typically separate ecosystems, each with its unique rules, native tokens, and often different consensus mechanisms. The ease with which transactions and interactions across several blockchains can occur may be restricted by this independence. By establishing links or facilitating interoperability across various networks, blockchain bridges overcome this restriction and allow assets and data to flow between them with ease.

How Blockchain Bridges Work

Here’s a brief overview of how blockchain bridges:

1. Locking of assets: A user starts a transaction on the source blockchain in order to move assets from one blockchain to another. The bridge's smart contract then keeps these assets "locked" or in escrow.

2. Confirmation: The transaction is validated and authenticated on the source blockchain by the bridge's smart contract.

3. Transaction verification: The role of oracles comes into play in bridges because they provide off-chain data to blockchain bridges’ smart contracts. They also verify the transaction details and confirm its execution.

4. Asset replica: Once transactions are confirmed, blockchain bridges create a representation of the locked assets on the destination blockchain, like a wrapped version of the assets. This representation can be in the form of tokens or other digital assets that mirror the original assets.

5. Release: On the destination blockchain, the receiver may now claim the transferred assets by supplying the required documentation or login credentials. The transfer procedure is finished when the bridge's smart contract unlocks the assets that were locked on the source blockchain.

Classes of Blockchain Bridges

1. Single Directional Bridges: These bridges facilitate one-way transfers of assets from one blockchain to another. For example, these types of bridges allow users to transfer Ethereum to Binance Smart Chain but not vice versa.

2. Bi-directional Bridges: Assets can flow freely between two blockchains in both directions thanks to bi-directional bridges. Assets can be moved back and forth between the networks that are bridged.

3. Multi-directional Bridges: By facilitating interoperability between different blockchains, these bridges make it possible to move assets between any two linked networks.

Applications of Blockchain Bridges

To enable easy transfer of assets.
To allow users to benefit from the advantages of other blockchains.
They make it possible for developers from various chains to work together.
Allow for positive feedback from other blockchains.

In conclusion, blockchain bridges are essential for breaking interoperability barriers and enabling smooth asset transfers and data exchanges between various blockchain networks, which opens up new avenues for decentralized ecosystems and applications.