Research on blockchain transaction protocols focuses on the design, analysis, and optimization of mechanisms that govern the transfer of assets and execution of operations in decentralized networks. These protocols define how transactions are created, validated, propagated, and recorded on the blockchain, ensuring consistency, integrity, and security across all nodes. Studies explore consensus-driven transaction ordering, transaction batching, atomic swaps, and payment channel protocols to enhance throughput, reduce latency, and prevent double-spending or fraud. Additionally, research investigates privacy-preserving transaction protocols, off-chain scaling solutions, and cross-chain interoperability to improve efficiency and user experience. Overall, blockchain transaction protocols are fundamental to the reliability, performance, and security of distributed ledger systems.