# CBDC Interoperability Flow

## Overview

CBDC interoperability enables cross-sovereign CBDC transfers through the CBDC Interoperability Matrix (CIM), including identity mapping, interledger conversion, and cross-certification.

## Prerequisites

- Source and destination CBDC systems are registered
- CIM service operational
- Identity mapping available
- Interledger conversion supported

## Visual Flow Diagram

```
┌─────────────┐
│ Cross-SCB   │
│ CBDC Transfer│
└──────┬──────┘
       │
       │ 1. Identity Mapping
       ▼
┌─────────────────────────┐
│ Map Cross-Sovereign    │
│  Identity               │
│  - CIM lookup           │
│  - Cross-certification  │
└──────┬──────────────────┘
       │
       │ 2. Interledger Conversion
       ▼
┌─────────────────────────┐
│ Convert Between Ledgers │
│  - Source CBDC format    │
│  - Target CBDC format    │
│  - Rate calculation      │
└──────┬──────────────────┘
       │
       │ 3. Execute Transfer
       ▼
┌─────────────────────────┐
│ Execute Cross-SCB      │
│  Transfer               │
└──────┬──────────────────┘
       │
       │ 4. Complete
       ▼
┌─────────────┐
│ Transfer    │
│  Complete   │
└─────────────┘
```

## Step-by-Step Process

### Step 1: Identity Mapping
1. Lookup source identity in CIM
2. Map to destination sovereign identity
3. Verify cross-certification
4. Validate KYC/AML standards

**Code Reference**: `src/core/cbdc/interoperability/cim-identity.service.ts`

### Step 2: Interledger Conversion
1. Determine conversion rate
2. Convert amount to target CBDC
3. Verify conversion parameters
4. Create conversion record

**Code Reference**: `src/core/cbdc/interoperability/cim-interledger.service.ts`

### Step 3: Execute Transfer
1. Post to source ledger (debit)
2. Post to destination ledger (credit)
3. Verify both postings
4. Create interoperability record

**Code Reference**: `src/core/cbdc/interoperability/cim-interledger.service.ts`

## Error Handling

- Identity mapping failure: Return error
- Conversion failure: Rollback, return error
- Transfer failure: Rollback both ledgers

## Integration Points

- CIM Identity Service: `src/core/cbdc/interoperability/cim-identity.service.ts`
- CIM Interledger Service: `src/core/cbdc/interoperability/cim-interledger.service.ts`

## Performance Metrics

- Total End-to-End: < 200ms target
- Throughput: 5,000+ conversions/second

---

**Related Flows**:
- [CBDC Wallet Transfer Flow](./cbdc-wallet-transfer-flow.md)
- [Identity Verification Flow](./identity-verification-flow.md)