sonr/docs/reference/modules/did.mdx

---
title: "Decentralized Identity"
description: "Sonr's Decentralized Identifier (DID) Module: W3C-Compliant Identity Management"
icon: "fingerprint"
sidebar:
  label: "Universal Identifiers"
  badge: "x/did"
---

The Sonr DID module implements a comprehensive W3C DID specification, providing a decentralized identity layer that enables self-sovereign identity management across the Sonr blockchain ecosystem.

## Key Features

- **W3C DID Documents**: Full implementation of the W3C DID Core specification
- **Verifiable Credentials**: Issue and manage W3C Verifiable Credentials
- **Multiple Verification Methods**: Support for various key types and WebAuthn
- **Signature Verification**: Multi-algorithm cryptographic signature verification
- **Service Endpoints**: Associate services with DIDs
- **Decentralized Resolution**: On-chain DID resolution without external dependencies

## Core Concepts

### Decentralized Identifiers (DIDs)

DIDs are globally unique identifiers created and controlled by their owners without requiring a central authority. In Sonr, DIDs follow the format: `did:sonr:<unique-identifier>`.

### DID Documents

DID Documents are core data structures containing:
- Verification methods (public keys, WebAuthn credentials)
- Service endpoints
- Controller relationships
- Authentication and verification relationships

### Verifiable Credentials

Digital credentials that can be cryptographically verified, containing claims about subjects and issued by trusted authorities.

## Revolutionary WebAuthn Integration

### Gasless WebAuthn Registration

The DID module introduces a groundbreaking **gasless registration** system that allows users to create their first decentralized identity without requiring any cryptocurrency. This removes traditional Web3 onboarding barriers.

#### Key Benefits
- **Zero Cost**: Create DIDs without tokens
- **Biometric Authentication**: Use device biometrics for identity creation
- **Instant Usability**: Immediate access to the Sonr ecosystem
- **Cross-Platform**: Works across all major browsers and operating systems

### CLI Usage Example

```bash
# Create DID with WebAuthn credential (no tokens required)
snrd auth register --username alice

# Register with automatic vault creation
snrd auth register --username bob --auto-vault
```

## Supported Verification Methods

1. **Ed25519**: High-performance, compact signatures
2. **JSON Web Signature**: Flexible web-compatible signature format
3. **WebAuthn**: Device-based authentication with biometrics
4. **ECDSA (Secp256k1)**: Blockchain-compatible signatures
5. **RSA**: Legacy system compatibility

## External Wallet Integration

Link external wallets like MetaMask and Keplr directly to your DID, enabling cross-platform identity management.

### Supported Wallet Types
- **Ethereum Wallets**: MetaMask, Coinbase Wallet
- **Cosmos Wallets**: Keplr, Leap Wallet, Cosmostation

## Security Considerations

- **Comprehensive Cryptographic Verification**
- **Origin Validation**
- **Anti-Replay Protection**
- **Credential Uniqueness Enforcement**

## Use Cases

- **Passwordless Authentication**
- **Cross-Platform Identity**
- **Verifiable Credentials**
- **Service Authentication**

## Standards Compliance

- W3C DID Core
- W3C Verifiable Credentials
- WebAuthn
- JSON-LD
- JSON Web Key/Signature

## Getting Started

### For Application Developers
1. Generate DID and initial document
2. Add verification methods
3. Register application services
4. Issue user credentials
5. Implement WebAuthn login

### For Wallet Developers
1. Implement DID resolution
2. Build credential management UI
3. Support WebAuthn authentication
4. Implement key recovery mechanisms

## Future Roadmap

- Off-chain DID resolution
- Zero-knowledge proof credentials
- Social key recovery
- Cross-chain DID interoperability
- Advanced credential schemas

## Documentation and Examples

Refer to the [Blockchain Documentation](/reference/concepts/sonr) for detailed guides, API references, and integration tutorials.