Certificates & Data Anchoring

Certificates are cryptographically signed, hash-based proofs that anchor digital records to the Circular network without exposing the underlying data. They enable secure, independently verifiable atte

Overview

In Circular, a certificate is a verifiable, immutable object created by hashing a digital asset (such as a document, dataset, or structured file), combining it with metadata, and anchoring the result to the network via a signed, timestamped record. Certificates serve as durable, privacy-preserving attestations for high-integrity processes.

They are designed for use in regulatory and operational settings, where data must remain under organizational control but still be provably unaltered and independently auditable.

Certificate Structure

Each certificate includes:

Field	Description
CertificateID	Deterministically generated unique identifier
IssuerID	Identity of the issuing node or organization
Hash	SHA-256 hash of the original file or payload
Metadata	Optional key-value fields defined at issuance
Timestamp	Logic timestamp assigned at the time of issuance
Signature	Issuer’s digital signature validating the certificate
ChainRef	Identifier for the blockchain where the certificate is anchored
BlockRef	Reference to the block containing the certificate

Certificates are immutable once issued and remain accessible for querying, verification, and auditing.

What Gets Anchored

Circular does not store the original data in the certificate or on the network. Only the cryptographic hash of the content is stored. This ensures:

• Data privacy is preserved

• Organizations retain full control of their files

• No sensitive or proprietary content is exposed

Anchored components include:

• Content hash

• Optional metadata

• Issuer and timestamp

• Network-level signature and anchoring reference

Signature and Verification

Every certificate is signed by the issuing node using a secure digital signature scheme. Circular currently supports:

Signature algorithm: EdDSA (Curve25519) or compatible elliptic curve options

Verification method: Deterministic hash-based verification using the issuer’s public key

To verify a certificate, the recipient re-hashes the original data and compares the output to the stored certificate hash. If the values match and the signature is valid, the certificate is considered authentic and unaltered.

Certificate Types

Circular supports different certificate classifications depending on context. Some predefined types include:

Type	Use Case
C_TYPE_DOC	General documents and PDFs
C_TYPE_DATASET	Research or analytical datasets
C_TYPE_MODEL	AI model outputs or configurations
C_TYPE_SIGNATURE	Timestamped digital approvals
C_TYPE_VOUCHER	Time-locked certificates with expiration logic

Each certificate type has an associated schema to ensure consistent formatting and usage.

Use Cases

Healthcare: Certify clinical trial results, lab records, or physician sign-offs

Pharmaceutical: Audit manufacturing batch integrity or protocol versioning

AI/ML: Anchor datasets or model checkpoints for reproducibility

Research & Academia: Timestamp and verify data submissions or publications

Legal & Governance: Prove authorship or attest to non-repudiation without revealing the underlying document

Access & Integration

Certificates can be accessed and managed via:

API:

Endpoints for certificate issuance, lookup, and validation

SDKs:

Available in supported programming languages for integration into internal workflows

Explorer:

Visual interface for inspecting issued certificates and verifying timestamps or issuers

Summary

Certificates are the atomic trust primitive within the Circular infrastructure. They provide a lightweight, secure mechanism for anchoring data without revealing it — enabling institutions to validate information, streamline audits, and protect integrity across collaborative environments.