Binance Bridge, Celer cBridge, and Wormhole are just some of the cross-chain bridges available today.
As the demand for different blockchain-based Web 3.0 technologies continues to grow, so does the need to achieve interoperability. This is achieved through cross-chain bridge services.
Blockchain is a distributed ledger technology that uses cryptography to provide assurance and integrity to data and transactions. Blockchain networks support many types of services, including secure databases, immutable ledgers, decentralized applications, decentralized finance, non-fungible tokens (NFTs), and cryptocurrencies.
There are many blockchain networks and cryptocurrencies that use different blockchain technologies, including Bitcoin, Ethereum, Avalanche, Polygon, Solana, and Arbitrum. Enabling interoperability and exchange between different blockchain networks is an area where cross-chain bridges (sometimes called blockchain bridges) play an increasingly important role.
What is a cross-chain bridge?
A cross-chain bridge enables the exchange of information, cryptocurrencies, or NFTs from one blockchain network to another. It supports the flow of data and tokens between isolated data sets on different blockchains.
With fiat currencies, individuals and businesses can exchange money in many established ways, creating a globally available and interoperable financial payment system. These systems include financial institutions that process foreign exchange, banks, and credit cards. In the blockchain world, cross-chain bridges serve a somewhat similar purpose.
Without a cross-chain bridge, it is possible to exchange cryptocurrencies between different blockchains, but it is expensive and time-consuming. Without using a cross-chain bridge, users must first convert cryptocurrency tokens into fiat currency, which often involves fees. They then use the currency to obtain the other desired type of cryptocurrency, incurring more fees and taking time.
One feature of a cross-chain bridge is that it enables users to exchange one cryptocurrency for another without first converting it to fiat currency. Cross-chain bridges are not limited to cryptocurrency value transfers either. An effective cross-chain bridge can also enable smart contracts and NFTs to be transferred from one blockchain environment to another.
There are several ways to enable transfers via cross-chain bridges. One common approach is to use wrapped tokens issued by a cross-chain bridge provider platform. With wrapped tokens, the value of one token from a specific blockchain network can be encapsulated in another token. Wrapped tokens are usually based on the ERC-20 technical specification of the Ethereum network. For example, WBTC is a Bitcoin token wrapped with an ERC-20 Ethereum smart contract.
Another way to enable cross-chain bridge transfers is to use liquidity pools. With liquidity pools, cross-chain bridge providers hold an inventory — or pool — of various coins and can exchange one coin for another.
Cross-chain bridges can also become lucrative targets for hackers. In February 2022, cross-chain bridging platform Wormhole fell victim to an attack that saw attackers steal 120,000 wrapped Ethereum tokens — worth an estimated $320 million at the time of the theft.
Learn more about how cryptocurrency cyberattacks are on the rise.
Bridge Best Cross-Chain
For Bitcoin, perhaps the most famous cryptocurrency, the most common bridge is using Wrapped Bitcoin (WBTC). Wrapped Bitcoin is sometimes called a blockchain bridge because it makes Bitcoin an ERC-20 token — a token specification that many other blockchains support.
While Bitcoin is well known, the Bitcoin blockchain does not have the same smart contract capabilities that underlie Ethereum-based blockchains. Smart contracts enable decentralized finance, decentralized applications, and NFTs. Users who wish to use Bitcoin on other blockchain networks will first need to convert to Wrapped Bitcoin. This was initially run by BitGo as a blockchain bridge and will be supported and used through a growing network of partner exchanges in 2022.
Cross-chain bridge providers typically support multiple types of blockchains, but specific support varies by provider. One of the most common features of cross-chain bridges is to support the introduction of smart contracts, tokens, and NFTs from the Ethereum mainline to different blockchain networks.
When choosing a cross-chain bridge, users should ensure that the specific blockchain network and token or NFT they wish to bridge is supported. Different networks also have different fees, which can be volatile and change quickly.
Here are some popular cross-chain bridges:
Binance Bridge
Binance Bridge has a wide set of options and can bridge a growing list of cryptocurrencies. The project is associated with the Binance Smart Chain blockchain project, which was rebranded as BNB Chain in February 2022. However, Binance Bridge is not limited to a single blockchain.
Supported blockchain networks: Ethereum, Solana, BNB Chain, and Tron
Website: https://www.bnbchain.world/en/bridge
Celer cBridge
Celer cBridge uses the Celer State Guardian Network to enable liquidity across different blockchains.
Supported blockchain networks: Ethereum, Astar, BNB Chain, Avalanche, Polygon, Arbitrum, Fantom, Metis Mainnet, Oasis Emerald, Celo, Aurora, Harmony, Moonbeam, Moonriver, Optimism, Boba Network, OKExChain, Heco, Clover, Gnosis Chain, Milkomeda Cardano, and Zidian.
Supported cryptocurrency tokens: Tether, USD Coin, Ethereum, MetisDAO, Kromatika, Binance USD, Thales, Domi Coin, Dodo, Unified Society, Lyra, JPEGvault, Immutable X, dForce, xToken, Wootrade, Perpetual Protocol, Mask Network, Izumi Finance, MCDex, PolkaEx, CEC Energy Chain, PerlinX, Reef Chain, Boba Network, and Standard Protocol.
Website: https://cbridge.celer.network
Cross-Chain Bridge
The platform was developed by the Germany-based Tixl organization, which changed its name to Autobahn Network in March 2022. Cross-Chain Bridge supports bridging tokens and NFTs across multiple networks.
Supported blockchain networks: Avalanche, BNB Chain, Polygon, Ethereum, and Fantom.
Supported cryptocurrency tokens: Bridge, Bulk Token, Candle, DAEX Token, GamyFi Platform, TribeOne, Moonie NFT, Polychain Monsters, Realm Token, Autobahn Network, UnitedCrowd Token, Unobtanium, Upfire, USD Coin, Tether, and Wrapped Ethereum.
Website: https://crosschainbridge.org
Umbria Narni Bridg
Umbria Narni Bridge uses liquidity pools to enable blockchain asset transfers where assets are held across multiple chains.
Supported blockchain networks: Polygon Mainnet, Ethereum Mainnet, BNB Chain, Avalanche. Planned support for Fantom, Ronin, Solana, Cardano, Immutable X, Worldwide Asset Exchange, Gnosis, KuCoin Community Chain, and Huobi Ecological Chain.
Supported cryptocurrency tokens: Ethereum, Polygon, USD Coin, Tether USD, Umbria Governance Token, and Wrapped Bitcoin.
Website: https://bridge.umbria.network
Multichain
Formerly known as Fantom Anyswap, Multichain positions itself as a cross-chain router protocol that supports the flow of data and assets across different blockchain networks. No other cross-chain bridging service supports as many token types as Multichain.
Supported blockchain networks: Arbitrum, Astar Network, Aurora, Avalanche, BNB Chain, Bitcoin, Blocknet, Boba Network, Celo, Clover, ColossusXT, Conflux eSpace, Cronos, Ethereum, Fantom, Fuse, Fusion, Gnosis, Harmony, Huobi, IoTex, KCC, Litecoin, Metis, Milkomeda, Moonbeam, Nebulas, OEC, Oasis Network, Optimism, Polygon, REI, Shiden Network, Syscoin NEVM, Telos, Terra, Velas, and XRP.
Website: https://multichain.org
Wormhole
Wormhole locks the original token through a smart contract and wraps the token in the Wormhole minted token on the target blockchain.
Supported blockchain networks: Solana, Ethereum, Terra, BNB Chain, Polygon, Avalanche, Oasis, and Fantom.
Supported cryptocurrency tokens: USD Coin, Tether, FTX Token, Ethereum, Serum, MakerDAO, TerraUSD, Binance USD, Huobi Global, OKEx, Frax Protocol Token, Huobi BTC, Synthetix, Shiba Inu, Axie Infinity, SushiSwap, Decentraland, The Sandbox, and Uniswap.
Website: https://portalbridge.com/#/transfer