From Paper Trails to Trust on Tracks: Adding Public Transparency to Railways via zk-SNARKs

2025-04-28

AI Summary

Lack of public transparency in railway regulation undermines stakeholder trust and hinders compliance auditing. To address this, we propose the first zero-knowledge verifiable digital system for railway infrastructure change processes, leveraging zk-SNARKs to simultaneously ensure regulatory compliance verification and privacy preservation. Our system enables end-to-end public verification—without exposing sensitive data (e.g., trade secrets or identities)—that multi-role, multi-step approvals adhere to prescribed regulatory rules. It integrates formal process modeling, an off-chain verification protocol, and digital signatures, marking the first systematic application of zk-SNARKs to process modeling in highly regulated domains. Evaluated on a real-world German railway approval scenario, the system supports workflows with over one thousand steps and achieves sub-second verification latency, demonstrating strong scalability. The framework is generalizable to other heavily regulated industries requiring auditable yet privacy-aware process governance.

Technology Category

• Data Mining & Knowledge Management: Representing, Reasoning, and Using Provenance, Trust
• Planning, Routing, and Scheduling: Plan Execution and Monitoring
• Application Domains: Transportation

Application Category

• Security and Privacy: Data transparency and provenance
• Systems and Infrastructure for Web, Mobile and WoT: Federated Web and WoT systems, including distributed, federated and edge-based data processing
• Responsible Web: Algorithmic accountability and transparency on the web

Abstract

Railways provide a critical service and operate under strict regulatory frameworks for implementing changes or upgrades. Despite their impact on the public, these frameworks do not define means or mechanisms for transparency towards the public, leading to reduced trust and complex tracking processes. We analyse the German guideline for railway-infrastructural modifications from proposal to approval, using the guideline as a motivating example for modelling decisions in processes using digital signatures and zero-knowledge proofs. Therein, a verifier can verify that a process was executed correctly by the involved parties and according to specification without learning confidential information such as trade secrets or identities of the participants. We validate our system by applying it to the railway process, demonstrating how it realises various rules, and we evaluate its scalability with increased process complexities. Our solution is not railway-specific but also applicable to other contexts, helping leverage zero-knowledge proofs for public transparency and trust.

Problem

• Enhancing public transparency in railway regulatory processes
• Ensuring correct process execution without revealing confidential data
• Applying zk-SNARKs for scalable trust in multi-party systems

Innovation

• Using zk-SNARKs for railway transparency
• Digital signatures verify process correctness
• Scalable zero-knowledge proof solution