2025-08-24 20:00 Tags:Web3

What are bridges?

Blockchain bridges work just like the bridges we know in the physical world. Just as a physical bridge connects two physical locations, a blockchain bridge connects two blockchain ecosystems. Bridges facilitate communication between blockchains through the transfer of information and assets.

Types of Blockchain Bridges:

1. Token Bridges:

   • Allow tokens (like ETH or USDT) to move between two blockchains (e.g., Bitcoin to Ethereum).

2. Data Bridges:

   • Facilitate the transfer of data or information between blockchains, not just assets.

3. Cross-chain Bridges:

   • Enable full interoperability between different blockchain ecosystems.

How Does It Work?

1. Locking on Blockchain A

• What happens: Imagine you have some tokens (say ETH) on Ethereum (Blockchain A) and you want to use them on a different blockchain, like Binance Smart Chain (BSC) (Blockchain B).

• How it works: To transfer ETH from Ethereum to BSC, you send the ETH to a bridge smart contract on Ethereum. This contract locks your ETH. It holds your ETH temporarily so that it can’t be used on Ethereum while it’s being transferred to BSC.

  Example:

  • You send 1 ETH to the bridge contract on Ethereum.

  • The 1 ETH is now locked and cannot be used or spent on Ethereum.

2. Minting/Issuance on Blockchain B

• What happens: Once your ETH is locked on Ethereum, the bridge protocol then creates an equivalent asset on Binance Smart Chain (BSC).

• How it works: The bridge creates a new token on BSC, say 1 Wrapped ETH (wETH). This wETH is now the same value as the ETH that is locked on Ethereum, but it’s now available for use on BSC.

  Example:

  • For every 1 ETH locked on Ethereum, the bridge mints 1 wETH on BSC.

  • This wETH can now be used on BSC-based apps or DeFi platforms.

3. Unwinding (Returning the Asset)

• What happens: If you want to return your ETH from BSC back to Ethereum, the wETH you minted on BSC is sent to the bridge contract, and it is burned (destroyed).

• How it works: When you send your wETH back to the bridge on BSC, the bridge burns the wETH (removes it permanently). This ensures that the supply of wETH doesn’t increase and the system stays balanced. After burning the wETH, the bridge will unlock your original ETH on Ethereum, making it available for you to use again.

  Example:

  • You send your 1 wETH from BSC to the bridge.

  • The bridge burns the 1 wETH on BSC.

  • It then releases the 1 ETH on Ethereum back to your wallet.

Summary:

A blockchain bridge is like a bridge connecting different blockchains, helping you safely transfer assets between them. It ensures that during the transfer process, no assets are created or lost, and the total supply remains balanced.