What is a cross-chain bridge?
DefinitionA cross-chain bridge is a protocol that moves value from one blockchain to another, for example from Ethereum to BNB Smart Chain. Blockchains can’t read each other directly, so the bridge locks, burns or swaps tokens on one side and releases them on the other.
How bridges work
A bridge connects two blockchains that can’t see each other’s balances. It uses smart contracts on both sides plus a mechanism, run by validators, a group of operators or cryptographic proofs, that confirms what happened on the source chain. Most bridges follow one of three designs:
- Lock and mint: your tokens are locked on chain A and a wrapped copy is minted on chain B; burning the copy unlocks the original
- Burn and mint: the token’s issuer burns it on one chain and mints the same amount on another
- Liquidity pools: you deposit on one chain and receive the same asset from a pool on the other, minus a fee
Wrapped tokens
A wrapped token is a claim on an asset locked somewhere else. Its value depends on the bridge keeping that asset safe: if the bridge is hacked or the backing runs short, the wrapped token can lose its value even while the original asset is fine.
That is why the same token name can mean different things on different networks. Check the token’s contract address and who stands behind it before you bridge or accept it.
Risks and costs
Bridging adds steps, and each one has a cost or a risk:
- Security: bridges hold large pools of funds and have been among the biggest targets of hacks in crypto
- Fees on both sides: a network fee on each chain, and often a bridge fee
- Time: from a few minutes to hours, and about a week for some official layer 2 withdrawals
- Wrong destination: sending to a network or address the bridge doesn’t support can lose funds
- Fake bridge sites: phishing copies of bridges ask for approvals that drain your wallet
Moving between networks in Waletifi
Waletifi’s cross-network transfer moves USDT between supported networks inside the app, where it is available, with the fees and the expected timing shown up front. You don’t have to search for a bridge website yourself, which is where fake copies wait.
