Web4 Claims and Verification

Conventions and TerminologyThe key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “NOT RECOMMENDED”, “MAY”, and “OPTIONAL” in this document are to be interpreted as described in BCP 14 when, and only when, they appear in all capitals, as shown here.

IntroductionThis document defines distinctions and lifecycle rules for claims, evidence, assessments, assertions, verification events, challenges, supersession, suspension, expiration, revocation, and receipts.

Core DistinctionsA Claim is a proposition about a subject. Evidence supports or opposes a claim. An Assessment is an evaluation under policy. An Assertion is an accountable signed statement. A Verification Event records checks. A Receipt records that an event occurred.Signed, verified, conformant, high assurance, and currently valid are distinct properties and MUST NOT be treated as synonyms.

Claim AssertionA claim assertion MUST identify the claim, subject, issuer, claim type or proposition, issuance time, policy context, status mechanism, and proof.{ "assertion_id": "urn:web4:claim:01JEXAMPLE", "assertion_type": "claim", "subject_id": "did:example:node-842", "issuer_id": "did:example:issuer-1", "claim_type": "urn:example:claim:operational-state", "claim_value": "active", "status_uri": "https://status.example/claims/01JEXAMPLE", "proof": { "type": "ExampleProof", "verification_method": "did:example:issuer-1#key-1", "value": "BASE64URL-SIGNATURE" } }

Verification EventsA verification event MUST identify the verifier, object checked, checks performed, policy, time, result, and proof. Success MUST NOT imply checks outside declared scope.

ChallengesA challenge MUST identify the challenged assertion, challenger, grounds, issue time, evidence where permitted, status, and proof.

Correction and SupersessionCorrection MUST preserve the original and issue a linked replacement. Supersession MUST NOT erase historical status or receipts.

Suspension, Expiration, and RevocationSuspension, expiration, and revocation are distinct. Verifiers MUST treat unresolved status as indeterminate.

LifecycleMaterial transitions MUST be authorized, integrity-protected, and recorded by a receipt.

ConformanceConformance does not require publication of a trust vector, reputation function, confidence graph, scoring model, or protected assessment method.

Relationship to Research ArtifactsBroader Web4 architectural work is described informatively in . Informative research materials MAY be published as versioned scholarly artifacts, including DOI-addressable records.A research artifact is not required for conformance unless expressly incorporated as a Normative Reference by a named profile. Referencing or verifying an artifact does not establish the truth of its conclusions, regulatory approval, certification, security, legal compliance, or IETF endorsement.A Conforming Implementation MUST NOT require access to KCoordinate, KQAS, or another protected internal assessment method unless a separate deployment agreement selects that implementation.

Security ConsiderationsImplementations MUST authenticate issuers, validate proof integrity, check proof purpose, enforce temporal validity, and resolve current status before relying on an object.Implementations MUST address identifier confusion, issuer impersonation, key compromise, algorithm downgrade, replay, stale status, unauthorized supersession, cross-policy confusion, canonicalization ambiguity, denial of service, and fail-open handling of indeterminate validity.Evidence commitments can confirm correspondence with committed bytes but do not prove truth, completeness, legality, provenance, or fitness for purpose. Profiles SHOULD define privacy-preserving commitment procedures for low-entropy artifacts.Proof verification establishes integrity and control of a verification method; it does not establish substantive truth.

Privacy ConsiderationsPersistent identifiers, status queries, proofs, policy references, and linked receipts can enable correlation. Implementations MUST minimize disclosed data and SHOULD use unlinkable or pairwise identifiers where they satisfy policy.Private evidence MAY remain undisclosed and be represented by a cryptographic commitment. Retention and erasure requirements MUST be specified by policy and account for applicable obligations.

IANA ConsiderationsThis document requests no IANA actions.