Cross-chain interoperability enables different blockchains to communicate and share data or assets. Key technical implementations include:
Bridges: Smart contracts or protocols (e.g., Wrapped Bitcoin) lock assets on one chain and mint equivalents on another, ensuring trust via validators or multi-signature schemes.
Atomic Swaps: Cryptographic hash time-locked contracts (HTLCs) allow trustless asset exchanges across chains, requiring both parties to fulfill conditions within a deadline.
Sidechains/Relays: Sidechains like Polygon or relays like Polkadot’s parachains use pegging mechanisms or shared security to transfer data/assets.
Oracles: Systems like Chainlink provide external data to facilitate cross-chain interactions.
Inter-Blockchain Communication (IBC): Protocols like Cosmos IBC standardize messaging for state and asset transfers.
Challenges include security risks (e.g., bridge hacks), latency, and consensus differences.