Cleveland Museum of Art · CC0 1.0A trace that no one can erase
OIMAP digital certification anchors the fingerprint of the paper certificate in a distributed registry, then in a public blockchain. It makes any modification detectable and lets anyone verify the document in a few seconds.
It does not replace the paper certificate: it accompanies it. The associated digital token is an access title to the file, never a title of ownership.
This page explains the technique, its advantages, its limits and how to verify a certificate.
Blockchain certification in figures
Source: OIMAP Observatory.
The principle of anchoring
Each OIMAP certificate is turned into a digital fingerprint, a unique string of characters that changes as soon as a single byte of the document is modified. This fingerprint, and not the document itself, is entered in a permissioned distributed registry operated by OIMAP, then time-stamped on a public blockchain.
Thus, no one can modify the certificate without the fingerprint changing, and no one can backdate or post-date its entry. Verification consists of recalculating the fingerprint of the document presented and comparing it with that in the registry.
What anchoring does not do
Anchoring proves the existence and integrity of a document at a given date. It proves neither the authenticity of the work, nor ownership, nor value. These questions are matters for expert examination, the title of ownership and valuation.
Anchoring also has no effect on the quality of the expert examination: a certificate based on a poor analysis remains based on a poor analysis, even if it is perfectly time-stamped. That is why digital certification is issued only on the basis of a paper certificate validated by the committee.
Interoperability and the future
OIMAP is working with international partners to make the fingerprints of its certificates interoperable with other registries: museums, insurers, customs administrations. The aim is for an anchored certificate to be verifiable by any system, without depending on a particular platform.
This openness is a condition of trust: a registry that only its operator can read adds little to a conventional database.
What each device proves
| Scheme | Proves | Does not prove |
|---|---|---|
| Paper certificate | Reasoned opinion of the expert | Digital integrity |
| Anchored fingerprint | Integrity and date | Authenticity of the work |
| Backed token | Right of access to the file | Ownership of the work |
| Title of ownership | Recognised ownership | Authenticity |
Landmarks
- First prototype
Internal registry.
- Public anchoring
Time-stamping on a public blockchain.
- Access token
Creation of the backed token.
- 1,247 certifications
10% of the total.
Energy and moderation
Permissioned registry or public blockchain
Permissioned registry
Operated by OIMAP- Fast and frugal
- Controlled access
- Clear governance
For managing certificates.
Public blockchain
Open to all- Independent of OIMAP
- Tamper-proof time-stamping
- More costly
For time-stamping.
Verifying an anchored certificate
- Obtain
Retrieve the document and its number.
- Calculate
Generate the file's fingerprint.
- Compare
Query the registry.
- Read
Check the anchoring date.
- Conclude
Validate or report.
Good practices
An engineer
« We do not trust the blockchain: we trust what it makes visible, the trace of a modification. »
Vocabulary of blockchain
- Fingerprint
- Unique result of a calculation on a file.
- Anchoring
- Entry of a fingerprint in a registry.
- Time-stamping
- Proof of the date of an event.
- Private key
- Secret allowing action on a token.
Frequently asked questions
Does the blockchain guarantee authenticity?
No, it guarantees integrity and date.
How do I verify?
Through the digital verification page.
What happens if I lose my key?
Access to the token is lost, but not the certificate.
Is the token transferable?
Yes, it passes with the work.
Useful documents
Contacts
Related pages
Digital market and NFTsThe market for digital works and backed tokens: regulation, blockchain certification and approved platforms.›
Digital certificationsA time-stamped fingerprint and a token backed by the paper certificate to follow a work's history without ever separating it from its file.›
VerificationCheck the authenticity of a digital certificate free of charge and without an account: number, QR code, file or token.›
See the regulation
Image credits (16)
- TLV Mirror with Multiple Nipples (9–23 CE) — Cleveland Museum of Art, CC0 1.0
- Rue du Regard, Eugène Atget (1899) — Cleveland Museum of Art, CC0 1.0
- Arion on a Sea Horse and Bacchante on a Panther (pair), William Adolphe Bouguereau (1855) — Cleveland Museum of Art, CC0 1.0
- An Indigo Factory, Allahabad, Louis-Théophile Marie Rousselet (1865–68, published 1869–70) — Cleveland Museum of Art, CC0 1.0
- Prayer Niche (Mihrab) (c. 1500s or mid-1900s) — Cleveland Museum of Art, CC0 1.0
- London Nomades, John Thomson (1877) — Cleveland Museum of Art, CC0 1.0
- Mirror with Concentric Circles, an Immortal, and Auspicious Animals (25–100 CE) — Cleveland Museum of Art, CC0 1.0
- Peregrine Falcons (Duck Hawks), John James Audubon (c. 1827) — Cleveland Museum of Art, CC0 1.0
- Historiated Initial (O) Excised from an Antiphonary: The Donor, Gorus Fucci, Kneels before Christ (c. 1300–1350) — Cleveland Museum of Art, CC0 1.0
- Arch in Farmyard, Swansea, Calvert Richard Jones (1845) — Cleveland Museum of Art, CC0 1.0
- Jar with Design in Underglaze Iron (1800s–1900s) — Cleveland Museum of Art, CC0 1.0
- Nowshera, Kashmir (number 1000), Samuel Bourne (1864) — Cleveland Museum of Art, CC0 1.0
- Lampas with foliate medallions in ogival lattice (1400s) — Cleveland Museum of Art, CC0 1.0
- Letter Box, Ogata Kōrin (1700s) — Cleveland Museum of Art, CC0 1.0
- Document Box (Ryōshibako) with Chrysanthemum and Plum (lid) (late 1800s-early 1900s) — Cleveland Museum of Art, CC0 1.0
- Flowers and Trees of the Four Seasons, Watanabe Shikō (early-mid 1700s) — Cleveland Museum of Art, CC0 1.0