# WIA-EDU-010 Student Data Standard v1.2

## Phase 3: Protocol & Synchronization

**Status:** ✅ Complete
**Version:** 1.2.0
**Date:** 2025-01-15
**Philosophy:** 弘益人間 (Benefit All Humanity)

---

## 1. Overview

Phase 3 introduces real-time synchronization, conflict resolution, and offline-first capabilities for student data systems. This phase enables seamless multi-device access and institutional data sharing.

## 2. Changes from v1.1

- Added real-time synchronization protocol
- Defined conflict resolution strategies
- Added offline-first architecture
- Specified data transfer protocols
- Added institutional data sharing framework
- Defined event streaming architecture

## 3. Synchronization Protocol

### 3.1 WebSocket Connection

**Endpoint:**
```
wss://sync.{institution}.edu/wia/v1/sync
```

**Connection Handshake:**
```json
{
  "action": "connect",
  "token": "Bearer {access_token}",
  "clientId": "client_abc123",
  "deviceId": "device_xyz789",
  "syncFrom": "2025-01-15T10:00:00Z"
}
```

**Server Response:**
```json
{
  "action": "connected",
  "syncId": "sync_123456",
  "serverTime": "2025-01-15T10:30:00Z",
  "pendingChanges": 42
}
```

### 3.2 Real-Time Updates

**Change Notification:**
```json
{
  "action": "change",
  "entity": "student",
  "operation": "update",
  "entityId": "2024-CS-001",
  "timestamp": "2025-01-15T10:30:15Z",
  "changes": {
    "email": {
      "old": "jane.old@university.edu",
      "new": "jane.smith@university.edu"
    }
  },
  "version": "v123",
  "author": "user_456"
}
```

## 4. Conflict Resolution

### 4.1 Operational Transformation

Use Operational Transformation (OT) for concurrent modifications.

**Conflict Example:**
```json
{
  "conflictId": "conflict_abc",
  "entity": "student",
  "entityId": "2024-CS-001",
  "field": "phone",
  "baseVersion": "v122",
  "changes": [
    {
      "version": "v123",
      "value": "+1-555-111-2222",
      "timestamp": "2025-01-15T10:30:00Z",
      "author": "user_123"
    },
    {
      "version": "v124",
      "value": "+1-555-333-4444",
      "timestamp": "2025-01-15T10:30:05Z",
      "author": "user_456"
    }
  ]
}
```

### 4.2 Resolution Strategies

1. **Last Write Wins (LWW):** Use most recent timestamp
2. **Manual Resolution:** Flag for human review
3. **Field-Level Merge:** Combine non-conflicting fields
4. **Priority-Based:** Higher authority wins

### 4.3 Conflict Notification

```json
{
  "action": "conflict",
  "conflictId": "conflict_abc",
  "requiresResolution": true,
  "resolutionStrategy": "manual",
  "conflictData": { }
}
```

## 5. Offline-First Architecture

### 5.1 Local Storage

- IndexedDB for structured data
- Service Worker for API caching
- Delta sync for bandwidth optimization

### 5.2 Sync Queue

```json
{
  "queueId": "queue_123",
  "operations": [
    {
      "id": "op_001",
      "action": "update",
      "entity": "student",
      "entityId": "2024-CS-001",
      "changes": { },
      "timestamp": "2025-01-15T10:25:00Z",
      "status": "pending"
    }
  ]
}
```

### 5.3 Sync Process

1. Client queues changes locally
2. When online, push changes to server
3. Server processes and responds
4. Client updates local state
5. Client pulls server changes
6. Conflicts resolved automatically or flagged

## 6. Data Transfer Protocol

### 6.1 Institution-to-Institution Transfer

**Transfer Request:**
```json
{
  "transferId": "transfer_abc123",
  "sourceInstitution": "university-a",
  "destinationInstitution": "university-b",
  "studentId": "2024-CS-001",
  "dataTypes": [
    "profile",
    "academic_records",
    "transcripts",
    "attendance"
  ],
  "authorizationCode": "AUTH-2025-XXYYZZ",
  "studentConsent": true,
  "consentTimestamp": "2025-01-15T09:00:00Z"
}
```

**Transfer Response:**
```json
{
  "transferId": "transfer_abc123",
  "status": "initiated",
  "estimatedCompletion": "2025-01-15T10:05:00Z",
  "trackingUrl": "https://transfer.wia.org/track/transfer_abc123"
}
```

### 6.2 Data Package Format

```json
{
  "packageId": "pkg_abc123",
  "version": "1.2.0",
  "standard": "WIA-EDU-010",
  "created": "2025-01-15T10:00:00Z",
  "sourceInstitution": {
    "id": "university-a",
    "name": "University A",
    "country": "US"
  },
  "encryption": {
    "algorithm": "AES-256-GCM",
    "keyId": "key_xyz789"
  },
  "signature": {
    "algorithm": "RSA-SHA256",
    "value": "base64_signature",
    "certificate": "base64_cert"
  },
  "data": {
    "student": { },
    "records": [ ],
    "transcripts": [ ]
  },
  "checksums": {
    "sha256": "hash_value"
  }
}
```

### 6.3 Transfer Security

- End-to-end encryption (AES-256-GCM)
- Digital signatures (RSA-SHA256)
- Certificate-based authentication
- Transfer authorization codes
- Audit logging at both institutions

## 7. Event Streaming

### 7.1 Event Stream API

```
GET /events/stream

Accept: text/event-stream
Authorization: Bearer {token}
```

**Event Format:**
```
event: student.updated
data: {"studentId": "2024-CS-001", "changes": {...}}
id: event_123
retry: 5000
```

### 7.2 Event Types

- `student.*` - Student profile events
- `record.*` - Academic record events
- `attendance.*` - Attendance events
- `privacy.*` - Privacy setting events
- `transfer.*` - Data transfer events

## 8. Delta Synchronization

### 8.1 Delta Request

```http
GET /students/{studentId}/delta?since=2025-01-15T10:00:00Z
```

**Delta Response:**
```json
{
  "deltaId": "delta_abc",
  "since": "2025-01-15T10:00:00Z",
  "until": "2025-01-15T10:30:00Z",
  "changes": [
    {
      "type": "update",
      "entity": "student",
      "entityId": "2024-CS-001",
      "field": "email",
      "oldValue": "old@email.com",
      "newValue": "new@email.com",
      "timestamp": "2025-01-15T10:15:00Z"
    }
  ],
  "hasMore": false
}
```

## 9. Bandwidth Optimization

### 9.1 Compression

- Gzip compression for API responses
- Binary Protocol Buffers for high-volume transfers
- Delta updates instead of full records

### 9.2 Selective Sync

```json
{
  "syncConfig": {
    "entities": ["student", "records"],
    "fields": ["firstName", "lastName", "email"],
    "since": "2025-01-15T10:00:00Z",
    "limit": 100
  }
}
```

## 10. Multi-Tenant Support

### 10.1 Tenant Isolation

- Separate databases per institution
- Encrypted at-rest with tenant-specific keys
- Row-level security policies

### 10.2 Cross-Tenant Transfer

- Requires explicit authorization
- Audit trail at both tenants
- GDPR-compliant transfer logs

## 11. Monitoring and Health

### 11.1 Health Check

```http
GET /health

{
  "status": "healthy",
  "version": "1.2.0",
  "services": {
    "database": "healthy",
    "sync": "healthy",
    "transfer": "healthy"
  },
  "timestamp": "2025-01-15T10:30:00Z"
}
```

### 11.2 Metrics

- Sync latency
- Conflict rate
- Transfer success rate
- Active connections
- Queue depth

---

**Philosophy:** 弘益人間 (Benefit All Humanity)

*Enabling seamless data synchronization while maintaining security and privacy.*

© 2025 MIT License