Paper 2026/686

Secure MSM Outsourcing Computation for Zero-knowledge Proof Generation

Abstract

Zero-knowledge proof (ZKP) schemes enable a prover to convince a verifier of the validity of a statement without revealing the underlying secret. These schemes have found extensive applications in secure communications, privacy-preserving transactions and blockchain technologies. However, the computational cost of proof generation remains a major obstacle to practical deployment. Although various acceleration techniques have been proposed, they often rely on specialized hardware that may not be locally available. A promising yet underexplored alternative is to offload computation to a more powerful third party, such as a cloud server, in a secure and efficient manner. Rather than outsourcing the entire proof generation process, selectively offloading the most computationally intensive operations offers greater flexibility and simplicity. In this work, we propose a secure outsourcing scheme for multi-scalar multiplication (MSM), which is the most computationally expensive operation in many widely used ZKP protocols. Our scheme enables users to delegate MSM computations to a server while preserving the confidentiality of the secret inputs (i.e., the scalars) and allowing verification of the server’s output. Our performance analysis shows that the proposed scheme significantly reduces the computational burden on the user while imposing only minimal overhead on the server.