Standards & Protocol Stack

Digital Identity · Standards Map

Digital Identity Credential Stack

A layered view of the choices available across verifiable credential ecosystems — highlighting foundational choices profiled by the EU Digital Identity Wallet (ARF).

Supported or profiled in EU Digital Identity Wallet Architecture & Reference Framework (ARF)
Layer / FunctionStandards & Specifications (Click to open)
Issuance Protocol
OpenID4VCI CHAPI DIDComm ISO/IEC 23220-3 W3C VC-API Aries RFC 0453 OAuth 2.0 Dynamic Client Reg (RFC 7591)
Doc Formats
SD-JWT-VC ISO mDoc (18013-5) W3C VC Data Integrity (JSON-LD) W3C VC-JWT (JOSE) AnonCreds BBS+ Signatures Claim 169 (MOSIP) ICAO DTC (Digital Travel Credential) CWT / CBOR (RFC 8392) X.509 Attribute Certificate ACDC (KERI)
Presentation Flow
OpenID4VP ISO/IEC 18013-5 (Device Retrieval) DCQL (Query Spec) DIF Presentation Exchange (PE) ISO/IEC 18013-7 (Online mDL) SIOPv2 DIDComm Present Proof
Holder Verification
Hardware Keystore / WSCD (Secure Enclave) KB-JWT (Key Binding) Device MAC / Signature (18013-5) Biometric / PIN (User Auth) WebAuthn / Passkeys (UV) FIDO2
Invocation
Universal / App Link Custom URL Scheme (e.g., openid4vp://) QR Code Digital Credentials API (W3C DC API) Android Intent App Clip / Instant App CSC API Wallet-Initiated Push
Transport
HTTP / HTTPS BLE (OpenID4VP / mDoc) NFC (ISO 14443 / NDEF Handover) Camera (Optical QR) NFC (CTAP) HTTP/3 (QUIC) WebSocket UWB
Trust (Parties)
ETSI Trust Lists (TSL / eIDAS 2.0 LOTL) X.509 PKI (QTSPs) OpenID Federation 1.0 IACA / VICAL (mDL) vLEI (GLEIF) did:web / did:webvh did:jwk did:key did:ebsi did:cheqd / did:ion
Credentials Status
IETF Token Status List W3C Bitstring Status List v1.0 Status List 2021 (W3C Legacy) MSO Revocation (18013-5) CRL / OCSP (X.509) Dynamic Revocation API (REST) Cryptographic Accumulators / SMT

Autonomous Economic Agents · Layered Stack

Agentic Commerce Protocols

A five-layer framework for autonomous economic agents — from cryptographic identity and tool execution interfaces up to discovery, multi-agent orchestration, and financial transactions.

5Commerce Layers
10Protocol Types
28Tracked Standards
21+Consortia & Labs
Primary industry standard / active production specification
Layer / FocusProtocols & Industry Standards (Click to open)
1. Application & Commerce
The transactional foundation: checkout, contracting, payment authorization, and settlement.
ACP (Agentic Commerce Protocol — OpenAI & Stripe) AP2 (Agent Payments Protocol) UCP (Universal Commerce Protocol) Mastercard Agent Pay Visa Intelligent Commerce (VIC / TAP) x402 (HTTP 402) L402 (Lightning) MPP (Machine Payment Protocol) Stripe Shared Payment Tokens
2. Orchestration & Intent
The cognitive core: intent parsing, task decomposition, and multi-agent coordination.
A2UI (Agent-to-User Interface) OpenAI Assistants Run & Thread Spec LangGraph Multi-Agent Protocol CrewAI Flow Protocols AG-UI (Agent-User Interaction) Semantic Kernel Planners
3. Coordination & Discovery
The network fabric: agent registries, capability advertising, and counterparty routing.
A2A (Agent2Agent — Google / Linux Foundation) Agent Cards (Metadata Discovery JSON) DIDComm Messaging v2 Agent Protocol (AI Engineer Foundation) BeeAI ACP (Agent Communication Protocol) ERC-8004 / Autonolas (On-Chain Registries)
4. Tool & Integration
The functional interface: accessing external tools, APIs, enterprise DBs, and legacy systems.
MCP (Model Context Protocol — Anthropic) OpenAPI 3.1 Function / Tool Calling JSON-RPC 2.0 (Agent Transport) GraphQL Agent Execution Layer REST Agent Adapters
5. Identity, Security & Privacy
The trust foundation: delegated agent authority, verifiable credentials, and hardware binding.
W3C Verifiable Credentials / SD-JWT-VC OAuth 2.1 / GNAP (Delegated Authority) FIDO2 / Passkeys (User Intent & Binding) SPIFFE / SPIRE (Workload Identity) Verifiable Intent (Mastercard) HTTP Message Signatures (RFC 9421)