This preprint is available in two versions: French (main_fr.pdf / main_fr.tex) and English (main_en.pdf / main_en.tex). The English abstract follows. For over one hundred and fifty years, all railway signalling architectures have rested on a single assumption: safety authority resides in the ground infrastructure. The network authorises; the train obeys. We question its necessity. The physical safety condition is a local property of the train and its environment, verifiable without external authorisation. We propose an architecture — AEGIS (Autonomous Embedded Ground-Independent Signalling) — in which neither primary safety nor installation coordination depends on a centralised ground authority: the ground provides certified data, the train reasons, and installation coordination is handled by a topologically partitioned distributed ledger. We examine the architectural properties arising from this inversion, the emergent properties of the resulting system, and the open questions this new paradigm generates.
Tarek Galal, Valeria Tisch, Katja Assaf, Andreas Polze
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.
Santiago Figueroa-Lorenzo, Jon Goya, Javier Añorga, Iñigo Adín · 6 authors
The European Union is moving toward the “smart” era having as one of the key topics the smart mobility. What is more, the European union (EU) is moving toward Mobility as a Service (MaaS). The key concept behind MaaS is the capability to offer both the traveler's mobility and goods' transport solutions based on travel needs. For example, unique payment methods, intermodal tickets, passenger services, freight transport services, etc. The introduction of new services implies the integration of many Internet-of-Things (IoT) sensors. At this point, security gains a key role in the railway sector. Considering an environment where sensor data are monitored from sensor events, and alarms are detected and emitted when events contain an anomaly, this document proposes the development of an alarms collection system, which ensures both traceability and privacy of these alarms. This system is based on Ethereum blockchain events-log, as an efficient storage mechanism, which guarantees that any railway entity can participate in the network, ensuring both entity security and information privacy.