Credential Schema Protocol

The Credential Schema Protocol is a technical standard developed by the Accountable Digital Identity Association (ADIA) that defines how credential schemas are published, updated, and managed within digital identity systems. This protocol enables standardized creation and management of verifiable credential templates across different identity providers and services.

The protocol provides a structured way to handle credential schemas through a set of defined commands and message formats. It allows issuers, digital address services (DAS), and regional directories (ARD) to publish and manage credential schemas while enabling service providers to search and utilize these schemas for verification purposes.

Key features include:

• Standardized schema publishing and management
• Version control for credential schemas
• Schema search and discovery capabilities
• Schema archival functionality
• Role-based access controls
• JSON-based message formats

Technical Overview:

1. Purpose and Scope:

• Defines protocol commands for publishing and managing credential schemas
• Establishes standard message formats for schema operations
• Enables interoperability between different identity system participants

2. Key Technical Specifications:

• Uses JSON message format for all protocol commands
• Implements four core protocol commands:
  • publish
  • update
  • search
  • archive
• Supports schema versioning and attribute definitions

3. Implementation Requirements:

• Must be implemented by:
  • Issuer Agents
  • DAS Agents
  • ARD Agents
• Requires support for defined roles:
  • Issuer - publishes custom schemas
  • DAS - manages schemas for issuers
  • ARD - manages regional schemas
  • AGD - manages global schemas

4. Security Considerations:

• Role-based access control for schema management
• Schema validation and verification
• Digital signatures for schema authenticity
• Secure message transport

5. Interoperability Features:

• Standardized message formats
• Common schema attribute definitions
• Cross-system schema discovery
• Version compatibility management

6. Current Adoption:

   Implemented as part of the ADIA ecosystem for managing verifiable credential schemas across different identity providers and services