SSIDO

SSIDO is an open-source project that combines Self-Sovereign Identity (SSI) with FIDO2 authentication protocols to create a passwordless authentication solution. The project extends traditional Public Key Infrastructure (PKI) by implementing a Decentralized Public Key Infrastructure (DPKI) built on core SSI concepts including W3C DIDs, DID Documents, and Verifiable Credentials.

The technical architecture consists of two main components:

• SSI Authenticator: A client-side edge agent that handles authentication requests using:
  • Mobile or desktop applications
  • Integration with SSI wallets
  • Support for WebAuthn protocol
• SSI Validator: A server-side component that:
  • Validates user DIDs through the SSI DPKI
  • Performs cryptographic operations
  • Manages authentication sessions via HTTP(S) and WebSocket connections

The project was selected to participate in the European Union's development of a Self-Sovereign Identity Framework under the Horizon 2020 program. SSIDO aims to bridge existing FIDO2 implementations with emerging SSI ecosystems by providing standard interfaces for authentication while maintaining the security and privacy benefits of both technologies. The solution supports various verifiable credential schemes and can be extended to enable Multi-Factor Authentication (MFA) capabilities.