Threshold Signature-Based Access Control for High-Value Transactions in Decentralized Treasury Systems

Abstract

High-value treasury transactions demand robust authorization mechanisms capable of resisting single-point compromise and ensuring strong cryptographic guarantees. Traditional centralized approval workflows expose treasury operations to insider threats, key compromise, and system downtime. To address these challenges, this paper proposes a threshold signature-based access control framework that decentralizes transaction authorization among multiple predefined stakeholders. The framework integrates Shamir’s Secret Sharing for secure key partitioning and Boneh–Lynn–Shacham (BLS) signatures for efficient aggregation, enabling collaborative approval without revealing private key components. A decentralized treasury workflow is implemented using smart contracts, allowing automated verification of threshold signatures and enforcing multi-party authorization policies. Simulation results demonstrate improved resilience against partial key compromise, enhanced fault tolerance under participant unavailability, and lower verification overhead compared to traditional multi-signature schemes. The system ensures integrity, non-repudiation, and distributed trust—key elements for financial environments managing large-scale asset transfers. This research highlights the viability of threshold signature cryptography for securing decentralized treasuries, reducing operational risk, and enabling policy-driven distributed governance for high-value digital assets.