# WIA-FIN-022: Open Banking Standard 🏦

> **오픈뱅킹 표준**
> World Certification Industry Association (WIA) Official Standard

[![License: MIT](https://img.shields.io/badge/License-MIT-green.svg)](https://opensource.org/licenses/MIT)
[![Standard: WIA-FIN-022](https://img.shields.io/badge/Standard-WIA--FIN--022-22c55e)](https://wia.org/standards/fin-022)
[![Version: 1.0.0](https://img.shields.io/badge/Version-1.0.0-blue)](https://github.com/WIA-Official/wia-standards)
[![TypeScript](https://img.shields.io/badge/TypeScript-5.3-blue)](https://www.typescriptlang.org/)

## 📋 Table of Contents

- [Overview](#overview)
- [Philosophy](#philosophy)
- [Features](#features)
- [Quick Start](#quick-start)
- [Directory Structure](#directory-structure)
- [Implementation Phases](#implementation-phases)
- [Standards & Specifications](#standards--specifications)
- [API & SDK](#api--sdk)
- [Interactive Tools](#interactive-tools)
- [Documentation](#documentation)
- [Use Cases](#use-cases)
- [Security](#security)
- [Contributing](#contributing)
- [License](#license)
- [Contact](#contact)

## Overview

WIA-FIN-022 is a comprehensive standard for Open Banking, providing complete specifications, APIs, tools, and documentation for implementing secure, scalable, and compliant open banking systems. This standard enables third-party providers to access financial account information and initiate payments with customer consent.

### What is Open Banking?

Open Banking is a financial services framework that enables third-party developers to build applications and services around financial institutions by providing secure, standardized API access to customer financial data and payment capabilities. This paradigm shift transforms how banks, fintechs, and customers interact with financial services.

### Why WIA-FIN-022?

- **Comprehensive Coverage**: From basic concepts to enterprise integration
- **PSD2 Compliant**: Full compliance with EU Payment Services Directive 2
- **Security First**: OAuth 2.0, SCA, eIDAS certificates, encryption
- **Developer Friendly**: Working SDKs, clear APIs, extensive documentation
- **Interoperable**: Compatible with major banks and payment systems
- **Future-Proof**: Designed for extensibility with VRP, DeFi, CBDC support

## Philosophy

**홍익인간 (弘益人間) (홍익인간) · Benefit All Humanity**

This standard is built on the principle of creating technology that benefits humanity. Open Banking should:
- Empower customers with control over their financial data
- Enable secure and transparent financial services
- Foster competition and innovation
- Be accessible regardless of technical expertise
- Support inclusive financial services for all

## Features

### 🏦 Account Information Services (AIS)

- **Account Aggregation**: View multiple bank accounts in one place
- **Balance Checking**: Real-time balance queries across accounts
- **Transaction History**: Detailed transaction data with filtering
- **Standing Orders**: View recurring payment setups
- **Direct Debits**: Monitor and manage direct debit mandates

### 💸 Payment Initiation Services (PIS)

- **Domestic Payments**: Initiate payments within same country
- **International Payments**: Cross-border transfers with FX
- **Bulk Payments**: Multiple payments in single batch
- **Payment Status**: Real-time payment tracking
- **Instant Settlement**: Sub-second payment confirmation

### 🔁 Variable Recurring Payments (VRP)

- **Flexible Limits**: Variable amounts within predefined parameters
- **Sweeping**: Automatic fund movements for optimization
- **Subscriptions**: Usage-based payment models
- **Automated Savings**: Rules-based savings automation

### 🔐 Security & Compliance

- **OAuth 2.0**: FAPI-compliant authorization
- **Strong Customer Authentication (SCA)**: PSD2 compliant 2FA
- **eIDAS Certificates**: QWAC and QSeal support
- **JWS Signing**: Request/response integrity verification
- **TLS 1.2+**: Encrypted transport layer
- **mTLS**: Mutual certificate authentication

### 🌐 Advanced Features

- **Real-Time Notifications**: Webhook support for events
- **GraphQL API**: Alternative query interface (v2.0)
- **AI Insights**: ML-powered financial recommendations
- **Carbon Tracking**: Environmental impact monitoring
- **CBDC Support**: Digital currency readiness (v2.0)

## Quick Start

### Installation

```bash
npm install @wia/open-banking-sdk
# or
yarn add @wia/open-banking-sdk
```

### Basic Usage

```typescript
import { OpenBankingClient } from '@wia/open-banking-sdk';

// Initialize client
const client = new OpenBankingClient({
  clientId: 'your-client-id',
  clientSecret: 'your-client-secret',
  certificatePath: './certs/qwac.pem',
  signingCertPath: './certs/qseal.pem',
  baseUrl: 'https://api.bank.example.com',
  environment: 'production'
});

// Create account access consent
const consent = await client.consents.create([
  'ReadAccountsDetail',
  'ReadBalances',
  'ReadTransactionsDetail'
], '2026-12-31T23:59:59Z');

// Get authorization URL
const authUrl = client.auth.getAuthorizationUrl({
  consentId: consent.ConsentId,
  redirectUri: 'https://yourapp.com/callback',
  scope: 'accounts',
  state: 'random-state-123'
});

// Redirect user to authUrl...

// After callback, exchange code for tokens
const tokens = await client.auth.exchangeCode(
  authorizationCode,
  'https://yourapp.com/callback'
);

// Get accounts
const accounts = await client.accounts.list(tokens.access_token);
console.log('Accounts:', accounts.Data.Account);

// Get account balances
const balances = await client.accounts.getBalances(
  accounts.Data.Account[0].AccountId,
  tokens.access_token
);
console.log('Balance:', balances.Data.Balance);
```

### Payment Initiation Example

```typescript
// Create payment consent
const paymentConsent = await client.payments.createConsent({
  InstructionIdentification: 'ACME-PAY-123',
  EndToEndIdentification: 'E2E-123',
  InstructedAmount: {
    Amount: '100.00',
    Currency: 'GBP'
  },
  CreditorAccount: {
    SchemeName: 'UK.OBIE.SortCodeAccountNumber',
    Identification: '08080021325698',
    Name: 'Coffee Shop Ltd'
  },
  RemittanceInformation: {
    Unstructured: 'Payment for order #12345'
  }
});

// Redirect user for authorization...
const authUrl = client.auth.getAuthorizationUrl({
  consentId: paymentConsent.ConsentId,
  redirectUri: 'https://yourapp.com/payment-callback',
  scope: 'payments',
  state: 'payment-state-456'
});

// After authorization, submit payment
const payment = await client.payments.submit(
  paymentConsent.ConsentId,
  paymentConsent.Initiation,
  tokens.access_token
);

console.log('Payment Status:', payment.Status);
```

## Directory Structure

```
open-banking/
├── index.html              # Landing page with overview
├── simulator/
│   └── index.html         # Interactive simulator (5 tabs)
├── ebook/
│   ├── en/                # English documentation
│   │   ├── index.html     # Table of contents
│   │   ├── chapter1.html  # Introduction to Open Banking
│   │   ├── chapter2.html  # Open Banking APIs
│   │   ├── chapter3.html  # Security and Authentication
│   │   ├── chapter4.html  # OAuth 2.0 and Consent Management
│   │   ├── chapter5.html  # Implementation Guide
│   │   ├── chapter6.html  # Third-Party Providers
│   │   ├── chapter7.html  # Case Studies and Best Practices
│   │   └── chapter8.html  # Future of Open Banking
│   └── ko/                # Korean documentation
│       └── (same structure as en/)
├── spec/
│   ├── WIA-FIN-022-spec-v1.0.md  # Core specification
│   ├── WIA-FIN-022-spec-v1.1.md  # VRP and enhancements
│   ├── WIA-FIN-022-spec-v1.2.md  # Advanced features
│   └── WIA-FIN-022-spec-v2.0.md  # Next generation (CBDC, DID)
├── api/
│   └── typescript/
│       ├── package.json
│       └── src/
│           ├── types.ts   # TypeScript type definitions
│           └── index.ts   # Main SDK implementation
└── README.md              # This file
```

## Implementation Phases

### Phase 1: API Foundation

Standardized RESTful APIs for account information, payment initiation, and confirmation of funds following PSD2 and Open Banking UK standards.

- Account Information API (AISP)
- Payment Initiation API (PISP)
- Confirmation of Funds API (CBPII)
- OAuth 2.0 authentication
- OpenAPI 3.0 specifications

### Phase 2: Security Layer

Comprehensive security framework including strong customer authentication, digital certificates, and encryption protocols for secure data exchange.

- Strong Customer Authentication (SCA)
- eIDAS qualified certificates
- TLS 1.2+ encryption
- JWS/JWE message signing
- Dynamic linking for payments

### Phase 3: TPP Integration

Third-Party Provider integration framework supporting Account Information Service Providers (AISPs) and Payment Initiation Service Providers (PISPs).

- TPP registration & onboarding
- Developer portal & sandbox
- API rate limiting & quotas
- Webhook notifications
- Analytics & monitoring

### Phase 4: Advanced Services

Next-generation services including variable recurring payments, bulk payments, and real-time data streaming for enhanced customer experiences.

- Variable Recurring Payments (VRP)
- Bulk payment processing
- Real-time account updates
- Premium API tiers
- Consent management dashboard

## Standards & Specifications

### Version 1.0 (Stable)

Core specification covering:
- Account Information Services
- Payment Initiation Services
- Confirmation of Funds
- Security requirements
- Error handling

[View Specification v1.0](./spec/WIA-FIN-022-spec-v1.0.md)

### Version 1.1 (Stable)

Enhanced features:
- Variable Recurring Payments (VRP)
- Bulk payment operations
- Enhanced security with JWS
- Real-time webhooks

[View Specification v1.1](./spec/WIA-FIN-022-spec-v1.1.md)

### Version 1.2 (Stable)

Advanced capabilities:
- International payments
- AI-powered transaction categorization
- Carbon footprint tracking
- Open Finance extensions (investments, pensions)

[View Specification v1.2](./spec/WIA-FIN-022-spec-v1.2.md)

### Version 2.0 (Beta)

Next generation:
- Quantum-resistant cryptography
- CBDC support
- Decentralized Identity (DID)
- GraphQL API
- Real-time settlement

[View Specification v2.0](./spec/WIA-FIN-022-spec-v2.0.md)

## API & SDK

### TypeScript SDK

Full-featured SDK for Node.js and browsers:

```bash
npm install @wia/open-banking-sdk
```

Features:
- Type-safe API with TypeScript definitions
- Promise-based async/await support
- OAuth 2.0 and FAPI compliance
- Certificate management
- Comprehensive error handling
- Event-driven architecture

[SDK Documentation](./api/typescript/README.md)

## Interactive Tools

### Simulator

Try Open Banking features without writing code:

[Launch Simulator](./simulator/index.html)

Features:
- 5-tab interface (Overview, Testing, Validation, Results, Integration)
- Account information testing
- Payment initiation simulation
- OAuth flow demonstration
- Security validation tools
- Integration code examples

## Documentation

Comprehensive guides and tutorials:

**English**: [View Documentation](./ebook/en/index.html)
**Korean**: [문서 보기](./ebook/ko/index.html)

Topics covered:
1. Introduction to Open Banking
2. Open Banking APIs
3. Security and Authentication
4. OAuth 2.0 and Consent Management
5. Implementation Guide
6. Third-Party Providers (TPPs)
7. Case Studies and Best Practices
8. Future of Open Banking

## Use Cases

### 💰 Account Aggregation

View all bank accounts, credit cards, loans, and investments in single application. Get complete financial picture without logging into multiple banking apps.

### 💸 Payment Initiation

E-commerce sites offer direct bank payments as alternative to cards, reducing transaction fees and improving conversion rates with streamlined checkout.

### 📱 Personal Finance Management

Apps automatically categorize transactions, track spending patterns, identify subscriptions, set budgets, and provide personalized financial advice.

### 💼 Business Banking

SMEs connect accounting software directly to bank accounts for automatic reconciliation, cash flow forecasting, and financial reporting.

### 🤖 AI Financial Insights

Power AI-driven financial advisors with real-time data. Personalized recommendations and automated savings strategies.

### 🌍 Cross-Border Payments

Low-fee international transfers with transparent FX rates and instant confirmation.

## Security

### Encryption

- **At Rest**: AES-256-GCM encryption for all stored data
- **In Transit**: TLS 1.3 for network communications
- **Key Derivation**: PBKDF2 with 100,000+ iterations

### Authentication

Multiple layers of security:
1. **OAuth 2.0**: FAPI-compliant authorization
2. **SCA**: Strong Customer Authentication with 2FA
3. **eIDAS**: Qualified certificates (QWAC, QSeal)
4. **mTLS**: Mutual certificate authentication

### Privacy

- Zero-knowledge proofs for anonymous credentials
- Selective disclosure of information
- GDPR and CCPA compliant
- Customer-controlled consent management

### Compliance

- **PSD2**: Full compliance with EU directive
- **Open Banking UK**: Compatible with UK standards
- **KYC/AML**: Identity verification and transaction monitoring
- **SOC 2**: Security and availability controls

## Contributing

We welcome contributions from the community! Here's how you can help:

### Reporting Issues

Found a bug or have a suggestion? Please [open an issue](https://github.com/WIA-Official/wia-standards/issues) on GitHub.

### Submitting Pull Requests

1. Fork the repository
2. Create a feature branch (`git checkout -b feature/amazing-feature`)
3. Commit your changes (`git commit -m 'Add amazing feature'`)
4. Push to the branch (`git push origin feature/amazing-feature`)
5. Open a Pull Request

### Development Guidelines

- Follow TypeScript best practices
- Write comprehensive tests
- Update documentation
- Follow semantic versioning

## License

This standard and its implementations are released under the [MIT License](LICENSE).

```
MIT License

Copyright (c) 2025 SmileStory Inc. / WIA

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
```

## Contact

- **Website**: https://wia.org
- **Email**: standards@wia.org
- **GitHub**: https://github.com/WIA-Official/wia-standards
- **Discord**: https://discord.gg/wia
- **Twitter**: @WIA_Official

## Acknowledgments

Special thanks to:
- Open Banking UK for pioneering standards
- European Banking Authority for PSD2 guidance
- All contributors to the WIA standards
- The open-source community
- Early adopters and testers

## Related Standards

- [WIA-FIN-001](../wia-fin-001/): Robo Advisor Standard
- [WIA-FIN-002](../blockchain-finance/): Blockchain Finance Standard
- [WIA-FIN-003](../cryptocurrency/): Cryptocurrency Standard
- [WIA-FIN-015](../digital-wallet/): Digital Wallet Standard

---

**홍익인간 (弘益人間) (홍익인간) · Benefit All Humanity**

© 2025 SmileStory Inc. / World Certification Industry Association (WIA)

Made with ❤️ for a more open and accessible financial future.