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StoriesSystem: Data provenance chain

From sensor to record

A published observation should carry its own history: which instrument made it, when, under which calibration, and every step since. The web already has a vocabulary for that history1; transparency logs make it tamper-evident2.

Systems
Signed readings, Transparency logs, Verifiable credentials
Toward 2030
Post-quantum signatures
Figures
3, systems diagram, timeline to 2030, data story

Go to the references

01Systems diagram

Every hop leaves a mark.

The sensor signs its reading; the gateway forwards it; the edge checks the signature, stamps the time and appends an entry to an append-only log whose Merkle tree lets anyone verify that nothing was removed or rewritten2. The publication carries a link back to that entry. Compromise the gateway and see which readings still arrive verifiable.

Scenario

Figure as text: A provenance chain from signed reading to publication

A four-tier diagram: sensors that sign, gateways, the edge with its transparency log, and publication and archive.

  • Signing sensors: Sensor 1, Sensor 2, Sensor 3
  • Gateways: Gateway A, Gateway B
  • Edge and log: Edge admission, Transparency log
  • Publication: Publication, Archive

10 links. Scenarios: All hops trusted; Gateway A compromised.

02Timeline to 2030

Words for where data came from.

PROV describes entities, the activities that generated them and the agents responsible1. Verifiable credentials let an instrument or an operator present signed claims, such as a calibration certificate, that others can check3; content credentials do the same for images and media4.

Figure as text: Provenance and transparency standards

A timeline from 2013 to 2030 with PROV-O, Certificate Transparency 2.0, the post-quantum signature standards and Verifiable Credentials 2.0.

  1. 2013-04 PROV ontology (W3C PROV-O). A W3C vocabulary for provenance.1
  2. 2021-12 Certificate Transparency 2.0 (RFC 9162). Merkle-tree logs with verifiable inclusion and consistency proofs.2
  3. 2024 Content credentials. Signed provenance manifests for media.4
  4. 2024-08 Post-quantum signatures standardised (FIPS 204, FIPS 205). Lattice and hash-based signatures published.5
  5. 2025-05 Verifiable Credentials 2.0 (W3C VC 2.0). Signed, machine-verifiable claims.3

03Data story

The cost of a signature.

Signing every reading costs bytes. A classical elliptic-curve signature is 64 bytes6; the post-quantum lattice signatures standardised in 2024 run to thousands5, and hash-based ones larger still7. For a sensor sending 20 bytes, that is a design question, not a footnote.

Figure as text: Signature sizes, classical and post-quantum

A bar chart of signature sizes: 64 bytes for ECDSA P-256 and Ed25519, 2,420 to 4,627 bytes for ML-DSA, and 7,856 bytes for SLH-DSA-128s.

Signature sizes, classical and post-quantum (bytes)
SchemeBytes
ECDSA P-25664
Ed2551964
ML-DSA-442,420
ML-DSA-653,309
ML-DSA-874,627
SLH-DSA-128s7,856

Figure 1

Systems diagram

Sources reaching a sink
3 of 3
Longest route
4 hops
State
All hops trusted

Figure 1. A provenance chain from signed reading to publication. A four-tier diagram: sensors that sign, gateways, the edge with its transparency log, and publication and archive.

References

  1. PROV-O: The PROV ontology. World Wide Web Consortium, 2013.
  2. RFC 9162: Certificate Transparency version 2.0. Internet Engineering Task Force, 2021.
  3. Verifiable Credentials Data Model v2.0. World Wide Web Consortium, 2025.
  4. C2PA technical specification: content credentials. Coalition for Content Provenance and Authenticity, 2024.
  5. FIPS 204: Module-Lattice-Based Digital Signature Standard. National Institute of Standards and Technology, 2024.
  6. RFC 8032: Edwards-curve digital signature algorithm (EdDSA). Internet Engineering Task Force, 2017.
  7. FIPS 205: Stateless Hash-Based Digital Signature Standard. National Institute of Standards and Technology, 2024.

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