Bridge

A blockchain bridge is infrastructure that allows tokens, data, and messages to move between separate blockchain networks. Without bridges, assets on Ethereum cannot interact with Solana, and vice versa. Bridges are essential for a multi-chain ecosystem.

How Bridges Work:

Lock-and-Mint Model: 1. User deposits tokens into a bridge contract on the source chain 2. The bridge verifies the deposit 3. Equivalent tokens are minted on the destination chain 4. To return, the minted tokens are burned and originals unlocked

Liquidity Pool Model: 1. Liquidity providers deposit tokens on both chains 2. Users swap from one chain's pool to another 3. No locking/minting, just rebalancing pools 4. Faster but limited by available liquidity

Types of Bridges:

Major Bridge Protocols: - LayerZero: Omnichain messaging protocol - Wormhole: Multi-chain token and message bridge - Across: Optimistic bridge with fast finality - IBC: Native bridge protocol for Cosmos ecosystem

Security Track Record: Bridges have been the most exploited category in crypto. Over $2.5B has been stolen from bridge exploits: - Ronin Bridge: $625M (2022) - Wormhole: $320M (2022) - Nomad: $190M (2022) - Multichain: $130M (2023)

Why Bridges Are Risky: They hold large amounts of locked tokens (attractive targets), rely on complex cross-chain communication, and often use multisig wallets that can be compromised. The security of a bridge is limited by its weakest link across two different chains.

The Future: Zero-knowledge proof bridges and native interoperability protocols aim to improve bridge security by replacing trust assumptions with mathematical verification.