Cross-chain communication: the "information superhighway" of the Web3 value internet

In 2024, the cross-chain gateway of Hong Kong HashKey Exchange processed more than 120,000 compliance transactions per day, supporting real-time interaction of 8 public chain assets such as Ethereum and Solana, verifying the infrastructure value of cross-chain communication in the Web3 era. As the core technology connecting different blockchains, cross-chain communication breaks down the "chain island" barrier through protocol design and technological innovation, enabling assets, data and smart contracts to flow across chains, and promoting the transition of the Internet from "information transmission" to "value transmission".

Technical principle: Breaking through the underlying logic of inter-chain barriers

Cross-chain communication achieves inter-chain interaction through multiple technical paths.

• Relays (Relays) : such as BTC Relay by listening to bitcoin network events, verify bitcoin transactions on Ethereum, to achieve cross-chain mapping of assets.
• Atomic Swaps (Atomic Swaps) : By using Hash Time Locked Contracts (HTLC), users can complete cross-chain asset exchange without trusting a third party. For example, users can directly exchange Bitcoin for Ethereum, and both parties ensure asset synchronization settlement through smart contracts.
• Cross-Chain Gateways (Cross-Chain Gateways) : The cross-chain gateway of HashKey Exchange adopts a distributed verification network. After users lock assets in the source chain, the gateway generates equivalent tokens in the target chain. In 2024, the amount of cross-border transfer processed exceeds 600 billion Hong Kong dollars, and the confirmation time of a single transaction is compressed to within 5 seconds.

The core challenge of cross-chain communication is to ensure the consistency of data between heterogeneous chains. For example, the Chainlink CCIP protocol verifies off-chain data through an oracle network, allowing smart contracts to call external APIs across chains, supporting DeFi protocols to achieve cross-chain lending - users can deposit collateral on Ethereum and lend stablecoins on the Avalanche chain without manually transferring assets throughout the process.

Core Protocol: The cornerstone of building a multi-chain ecosystem

Cosmos' Cross-Chain Communication Protocol (IBC) adopts a "Hub-Zone" architecture, which verifies cross-chain transactions through Light Client. Each blockchain (Zone) can run independently and interoperate with other chains through IBC. For example, Cosmos Hub serves as the core hub, connecting multiple independent Zones to achieve cross-chain circulation of ATOM tokens and other assets. After the compliance framework of HashKey Exchange is connected to IBC, it will process more than 180 million supply chain traceability data interactions in 2024, ensuring trustworthy authentication throughout the entire process of cross-border goods.

Polkadot's Cross-Consensus Messaging Protocol (XCMP) allows parallel chains to communicate directly through relay chains. Parallel chains share the security of relay chains while maintaining independent governance. For example, NFT platforms can mint NFTs on a parallel chain, transfer assets across chains to DeFi parallel chains for mortgage lending through the XCMP protocol, and reduce gas fees by 70%.

The LayerZero protocol achieves cross-chain messaging through "full-chain nodes". Developers can quickly deploy cross-chain applications without adapting to multiple chain APIs. For example, after a certain DeFi protocol uses LayerZero, users can call the liquidity pool of other chains on any chain, and the transaction confirmation time is shortened to 2 seconds.

Application scenarios: from asset interconnection to ecological collaboration

Cross-chain communication has completely changed the way digital assets are circulated. Users can seamlessly transfer assets such as Bitcoin and Ethereum to the Solana chain through the cross-chain wallet of HashKey Exchange to participate in the DePIN (decentralized physical infrastructure) ecosystem. By 2024, the amount of cross-chain transactions processed will increase by 300%, and transaction fees will be reduced by 70%.

Cross-chain protocols enable DeFi applications to break through single-chain limitations. For example, the Aave protocol accesses multiple chains through CCIP. Users can deposit USDC in the Polygon chain and lend ETH on the Arbitrum chain, achieving liquidity optimization of "one deposit, multiple loans". In 2024, the total lock-up volume of cross-chain DeFi will exceed $200 billion, which is four times higher than the single-chain model.

Cross-chain trading of NFTs has become possible. OpenSea integrates cross-chain protocols, allowing users to mint NFTs on Ethereum, transfer them to the Flow chain for in-game use, or auction them on the Solana chain, expanding the application scenarios and market value of NFTs.