did:icon

The did:icon method is a blockchain-based DID implementation built on the ICON Network, designed to provide unique identifiers for people, organizations, and digital devices across interconnected communities. This method leverages the ICON blockchain's infrastructure to manage decentralized identifiers and their associated DID Documents.

The method uses a Smart Contract-based architecture where DIDs are managed through blockchain transactions. Each did:icon identifier includes a network identifier and a specific identifier string derived from transaction hashes, with an added checksum for error prevention. The system supports standard CRUD operations through blockchain transactions, allowing entities to create, read, update, and delete their DIDs.

Key features include:

• Blockchain-anchored security
• Multi-key management capabilities
• Network-specific identifiers for different ICON environments
• Checksum verification to prevent typing errors
• JSON Web Signature (JWS) based authentication
• Secp256k1 cryptographic support

Technical Implementation:

1. DID Generation and Structure:

• Format: did:icon:<network-id>:<specific-idstring>
• Network ID must be even-numbered hex digits (minimum 2)
• Specific ID combines:
  • idstring: First 20 bytes of transaction hash
  • checksum: 4-byte SHA3-256 hash

2. Resolution Process:

{
  "method": "read",
  "params": {
    "did": "<DID to Query>"
  }
}

• Queries executed through Smart Contract
• Returns complete DID Document with:
  • Public keys
  • Authentication methods
  • Creation/update timestamps

3. Key Management:

• Supports multiple public keys
• Uses Secp256k1VerificationKey type
• Key operations:
  • Addition via addKey
  • Revocation via revokeKey
• Authentication through JWS with ES256K algorithm

4. Technology Stack:

• Primary Components:
  • ICON Blockchain
  • Smart Contracts
  • Secp256k1 cryptography
  • JSON Web Signatures

5. Security Features:

• Transaction-based operations
• Checksum verification
• Multi-signature support
• Revocation mechanisms
• Blockchain-level immutability

The method implements standard W3C DID specifications while leveraging ICON's blockchain infrastructure for security and persistence.