Different Types of Blockchain Bridges
A blockchain bridge is a tool that allows the movement of crypto assets from one blockchain to another. These bridges can also move assets from layer 1’s to layer 2’s. Bridges are a key step to obtaining interoperability between different blockchains, and more than that, they allow users to benefit from the advantages some blockchains have over others. Bridges in cryptocurrency have become so widespread that many simple applications, like transactions, may run across bridges. Moreover, bridges themselves come in different forms, each tailored to a certain application or need. Here are a few examples of some different types of bridges:
- Trusted vs. Trustless: To start off, the two big bridge categories are trusted and trustless. All other bridge types fall within these two categories
- Trusted: A trusted bridge uses a third party/intermediary to serve as the go-between when transferring assets. This intermediary serves to verify and approve transactions. Trust-based bridges offer a speedy and cheap, as compared to trustless bridges, option when transferring assets across blockchains. However, the major downside to trusted bridges is that they are centralized, so they have security issues that could lead to a loss of assets on the user side.
- Trustless Bridges: Trustless bridges are essentially a decentralized bridge. This bridge is built similarly to an actual blockchain, where validators verify each transaction. As a result of this decentralized system, trustless bridges are far more secure than Trust-based bridges. This comes at the cost of some speed and price.
After these two large groups, there are several bridges that each have a more specific purpose.
- Cross-Chain Bridges: A cross-chain bridge is simply a bridge that connects two blockchains. For example, a bridge that connects Bitcoin to Ethereum. One of the most basic applications of this bridge is to trade one type of crypto for another. Many cross-chain bridges use trustless mechanisms.
- Federated Bridges: Like a cross-chain bridge, a federated bridge connects two blockchains. However, the difference lies in centralization, a group of validators or entities verifies each transaction. This trust-based model differs from the cross-chain bridge’s trustless model. As for their application, Federated Bridges do simple tasks like carrying out transactions, moving assets, deploying smart contracts, etc.
- Sidechain Bridges: Many sidechains operate independently of the mainnet. For this reason, there needs to be a bridge to connect them to the main blockchain. Sidechain bridges were designed specifically for this purpose: to connect the sidechain to the main blockchain. These bridges use their own consensus mechanism, like an actual blockchain. Furthermore, a sidechain doesn’t post data back to the main blockchain, so data from transactions isn’t sent along the bridge.
- Layer 2 Bridges: Like a sidechain bridge, a Layer 2 bridge serves to connect the main blockchain to Layer 2. Regarding it’s application, Layer 2 bridges simply process transactions, move assets, and deploy smart contracts. The difference between Layer 2 bridges and Sidechain bridges is that Layer 2’s must send data on transactions back to the main blockchain. Therefore, these bridges typically send the data back to the main blockchain to be verified.
If you want to learn more, check out the links below:
What Is Bridging in Crypto? A Complete Overview + AnalogyThank You for Reading
Blockchain bridges: Guide to cross-chain data sharing
If you like this article, consider reading my other articles
