W3C's 2025 standards for Verifiable Credentials (VCs) and Presentations (VPs) ensure cryptographic security, interoperability,

Summary of W3C Verifiable Credentials (VCs) and Presentations (VPs) Standards

Introduction

The W3C Candidate Recommendation (2025) standardizes cryptographic security for Verifiable Credentials (VCs) and Verifiable Presentations (VPs) using JOSE/JWS (signatures), SD-JWT (selective disclosure), and COSE (binary efficiency). The standards ensure integrity, authenticity, and selective disclosure, while promoting interoperability through normative rules, security protocols, and media type guidelines.

Main Sections

Section 1: Core Standards and Security

Encoding Formats: Supports JWT, SD-JWT (for selective disclosure), and COSE, aligning with VC Data Model 2.0.
Normative Rules: Defines media types (e.g., vc+jwt, vp+sd-jwt), prohibits unsigned tokens (alg: "none"), and requires public/private key verification.
Security: Mandates JWS for integrity, optional JWE encryption for insecure channels, and JSON-LD compliance.

Section 2: JWT and SD-JWT Implementation

JWT Structure: Headers (alg, kid), payload (issuer, subject), and signature.
SD-JWT: Enables selective disclosure via SD-JWT~disclosures~KB-JWT structure; critical VC properties (e.g., @context) must remain non-disclosable.
Conflict Avoidance: Prevents clashes between JWT claims (e.g., iss) and VC properties (e.g., issuer).

Section 3: COSE Integration

Binary Efficiency: Uses COSE (application/vc+cose, application/vp+cose) for compact encoding.
Signing: Requires COSE_Sign1 for JSON-LD credentials; headers must include typ: application/vc+cose.
Encryption: Optional for insecure channels (RFC 9052).

Section 4: Media Types and Interoperability

Registered Types: vc+jwt, vp+jwt, vc+sd-jwt, vp+sd-jwt, vc+cose, and vp+cose.
Governance: Managed by W3C VC Working Group; no additional parameters or extensions defined.
Serialization: Compact JWS required; JSON serialization discouraged.

Section 5: Privacy and Accessibility

Privacy: Emphasizes data minimization, informed consent, and strong encryption (NIST SP 800-122).
Accessibility: Complies with WCAG 2.1, ensuring cryptographic tools do not interfere with assistive technologies.

Section 6: Examples and Use Cases

Revocable VCs: Uses StatusList2021Entry for revocation; supports multi-subject credentials.
Structured Disclosures: SHA-256 hashing for integrity, base64-encoded selective disclosures.
COSE Examples: Human-readable CBOR Diagnostic Notation for clarity, converted to binary for transmission.

Conclusion

The W3C standards provide a comprehensive framework for secure, interoperable VCs and VPs, leveraging JOSE, SD-JWT, and COSE. Key achievements include standardized media types, cryptographic integrity, selective disclosure, and compliance with privacy/accessibility guidelines. These specifications enable decentralized identity systems with verifiable, machine-readable credentials while minimizing data exposure.