1 · The problem

Who can prove what happened in a shared data space, months later?

In a data space, hospitals, telecoms, cloud operators and integrators work together but keep separate systems. Months later an auditor, a regulator, a partner in a dispute or a customer asks: what happened in your domain, and when? Today there are two bad answers.

Trust the platform's logs

The logs belong to somebody else. Whoever owns the platform can rewrite them. A record that nobody else can check is not evidence.

Or hand over your data

A central party could hold everyone's records. Nobody wants that: for privacy, for competition, for liability.

A handover falls between two books

A service offered by one organisation and accepted by another is recorded twice, in two systems. Neither side can show the claim between them without opening its own book.

2 · The solution

Every domain keeps its book. Only 32 bytes leave.

A third option. Each organisation keeps its events and its book at home. Once per period it publishes one 32-byte fingerprint of that period to a shared evidence rail that no single party — COTRUGLI Tech included — can rewrite. No records, no amounts, no identities, no telemetry leave the building.

Record at homeThe domain keeps its operational events in its own local book, next to its own systems. Documents, keys and custody never move.

Close a period, sign a fingerprintAt the end of a period with activity, the book seals into one 32-byte fingerprint. The domain signs it and links it to the previous one, so every period follows the one before.

The hub relays exactly 32 bytesThe hub checks the signature and the chain and recomputes the fingerprint byte for byte. It never sees an event. It relays exactly those 32 bytes to the rail and keeps the signed receipt: one receipt per closed period, never per event.

Prove any record, or a handover, laterThe domain can prove that any single record of that period existed, in that form, at that time — offline, with anyone's calculator, even if the platform or the hub disappears. Two domains can prove a handover between them without either opening its book.

In one sentence

A public, witnessed answer to "who did what, when" — that belongs to the domain, not to the infrastructure.

3 · The value

Audit readiness as a by-product

For the regulator and the auditorEvidence the domain already produces

AI Act, health-data and contractual obligations are met by evidence the domain already produces, at the cost of a few hundred bytes a day, not a data-sharing agreement. Any record can be checked against the rail without the platform's help.

For the partner organisationSovereignty stays with you

Keys, data and custody never move. The evidence survives a change of platform, provider or consortium — it belongs to the domain, not to the infrastructure. Onboarding is one container next to your own systems; nothing changes for the others.

For the consortiumDisputes get shorter

The question "who did what, when" has a public, third-party-witnessed answer that both sides can check; nobody needs to trust the other side's logs. Ten domains or ten thousand is the same shape — the rail carries fingerprints, not data.

For the Ambiti8n architectsA capability placed in the reference architecture

The evidence network supports the Data Layer of ICRA 3.0, with connections to Federation (a linked handover across two domains) and to Security and Compliance (signed envelopes, verifiable fingerprints). A proposed mapping of demonstrated capabilities, prepared for discussion.

4 · One pilot, three pages — the rehearsal and a local run

Nine domains. One rail. 32 bytes per period.

Nine execution domains on COTRUGLI Tech's own machines, labelled with partner names, closed eleven periods on 3–4 September 2026. Seventy-seven local records stayed local. Eleven 32-byte fingerprints went to the rail: 11 of 11 closed, 0 pending, every one at a witnessed public position with two witnesses. One handover was proven between two domains. Two pages show that rehearsal; a third shows a separate local run with ten contributors.

Pilot 1 — the network at day-close

Every closed period end to end: domain, period, fingerprint, receipt, position and witnesses, read from the evidence files. Eleven fingerprints, 352 bytes in total — 32 per fingerprint, never one 352-byte object.

Pilot 2 — one handover, two books

A guided walk, published 7 September 2026, through the actual pair from the rehearsal: offered in one domain's period, accepted in another's, exposed only after both fingerprints were on the rail. Plus the mapping to ICRA 3.0.

Pilot 3 — ten contributors, one shared case

A Chamber-side adapter rebuilds one shared case from ten contributors held in three separate sealed packages. Press the buttons: a changed record, a missing contributor, an unknown contributor, a wrong position — each one changes the verdict to "Not fully verified". 8 of 8 controls passed.

What is real

The domains and contributors are synthetic, run by COTRUGLI Tech on its own machines — no named organisation has installed, approved or operated a node. The rail closures, receipts, witnessed positions and the handover pair are recorded evidence from 3–4 September 2026, read from the linked files; Pilot 2 presents that same evidence with no new run, and Pilot 3 replays the saved results of a local run without live network sessions. The hub and edge hosts are powered off; a 24-hour run and continuous hourly production have not yet been shown.

LIVE — NEO RailRECORDED EVIDENCE — Rehearsal 3–4 September 2026RECORDED EVIDENCE — Pilot 3 local run, 8/8 controlsSIMULATED DOMAINS — nine partner-labelled nodes on COTRUGLI Tech machinesREFERENCE ARCHITECTURE — ICRA 3.0 mapping, proposed

Open the demo →

NEO Partner Evidence Network — COTRUGLI Tech's rehearsal for the Ambiti8n (IPCEI-CIS) partner pilot: observed, not promised. Next: a 24-hour run with a fresh start, its journals exported whole and stated plainly.