did:psi

type

DID Method

Specification

github.com

Contact Name

Police Science Institution

Contact Website

psi.go.kr

Info

Name, Specification URL, Contact name and some relations are sourced from diddirectory.com. If you maintain this or any other didmethod, we encourage you to visit diddirectory and submit or update your data there if its not up to date!

Description −

The did:psi method is a decentralized identifier system developed by the Police Science Institute of Korea for public security research and privacy protection. This method focuses on enabling Self-Sovereign Identity while protecting user privacy in social science and crime prevention contexts.

The method uses a blockchain-based architecture but stores only public key information, avoiding any personally identifiable information (PII) on-chain. The system is designed to support core SSI operations including authentication, encryption, issuance, and verification while maintaining data confidentiality and integrity.

Key features include:

Base58 encoding for identifiers to improve readability
Blockchain-based DID Document storage
Permission-based access control for CRUD operations
End-to-end encryption for data sharing
Support for multiple verification relationships
No storage of personal information on-chain

Technical Implementation:

DID Generation and Structure:

Format: did:psi:<base58-identifier>
Identifier length: 21-22 characters
Uses Base58 encoding with 16 bytes of UUID
Regex pattern: ^(did:psi:(?:[1-9A-HJ-NP-Za-km-z]{21,22}))$

Resolution Process:

Implements a dedicated did:psi resolver
Returns W3C-compliant DID Documents
Converts internal blockchain storage format to standard DID Document format

Key Management:

Uses EcdsaSecp256k1VerificationKey2019 for cryptographic operations
Supports multiple verification methods:
- Authentication
- Assertion Method
- Key Agreement
Implements separate key update mechanisms for:
- verificationMethod
- verificationRelationship

Technology Stack:

Built on blockchain infrastructure
Uses smart contracts for DID operations
Implements BigInt conversion for efficient UUID storage
Requires blockchain account creation as prerequisite

Security Features:

Permission-based access control
Signature verification for operation authorization
No PII storage on blockchain
End-to-end encryption for data sharing
Controller-based authorization model

The method implements standard CRUD operations through the following endpoints:

did contract/newaccount   // Account creation
did contract/regdid       // DID creation
did contract/updatekeys   // Key updates
did contract/deletedid    // DID deactivation