Thetacrypt: A Distributed Service for Threshold Cryptography

2025-02-05

AI Summary

This paper addresses the fragmentation of threshold cryptography schemes, their integration challenges, and the lack of distributed performance evaluation. We propose Thetacrypt—a language-agnostic, modular, unified threshold cryptographic service framework. Methodologically, we achieve architecture-level integration of six fundamental schemes—including Shamir’s secret sharing, Feldman’s verifiable secret sharing (VSS), and the GG20 multi-party signature protocol—abstracting a unified protocol interface, embedding P2P communication and total-order broadcast channels, and building a controllable distributed testbed. Our contributions are threefold: (1) the first threshold cryptographic middleware supporting collaborative deployment of heterogeneous schemes; (2) empirical characterization of how network latency and synchronization assumptions critically impact throughput and end-to-end latency—filling a gap left by traditional micro-benchmarks that ignore distributed-systems characteristics; and (3) an open-source, extensible library enabling plug-and-play threshold cryptographic capabilities for distributed systems.

Technology Category

• Constraint Satisfaction and Optimization: Distributed CSP/Optimization
• Search and Optimization: Distributed Search
• Planning, Routing, and Scheduling: Scheduling under Uncertainty

Application Category

• Security and Privacy: Applications of cryptography
• Systems and Infrastructure for Web, Mobile and WoT: Experiences and lessons learnt from Web-based algorithms and system deployments
• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems

Abstract

Threshold cryptography is a powerful and well-known technique with many applications to systems relying on distributed trust. It has recently emerged also as a solution to challenges in blockchain: frontrunning prevention, managing wallet keys, and generating randomness. This work presents Thetacrypt, a versatile library for integrating many threshold schemes into one codebase. It offers a way to easily build distributed systems using threshold cryptography and is agnostic to their implementation language. The architecture of Thetacrypt supports diverse protocols uniformly. The library currently includes six cryptographic schemes that span ciphers, signatures, and randomness generation. The library additionally contains a flexible adapter to an underlying networking layer that provides peer-to-peer communication and a total-order broadcast channel; the latter can be implemented by distributed ledgers, for instance. Thetacrypt serves as a controlled testbed for evaluating the performance of multiple threshold-cryptographic schemes under consistent conditions, showing how the traditional micro benchmarking approach neglects the distributed nature of the protocols and its relevance when considering system performance.

Problem

• Integrates multiple threshold cryptography schemes
• Facilitates distributed systems with threshold cryptography
• Evaluates performance of cryptographic schemes consistently

Innovation

• Versatile library for threshold cryptography
• Supports diverse cryptographic protocols uniformly
• Includes flexible adapter for peer-to-peer communication