Multi-Device and Role Management

Learn about YAT's Actor model and multi-device collaboration mechanism

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📋 Table of Contents

• Actor Model Overview
• Role Definitions
• Multi-Device Collaboration
• Session Management
• Device Management
• FAQ

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Actor Model Overview

What is Actor Model?

YAT uses Actor model to manage multi-device collaboration. Each device plays a role (Actor) in the tunnel, working together to complete remote access tasks.

Why Need Actor Model?

Scenario Example:

Office computer ──wants to access──► Home Mac

Traditional solution:
- Cannot distinguish who is accessing
- Cannot control permissions
- Confused state

YAT Actor Model:
- Office computer = Consumer
- Home Mac = Publisher
- Clear roles, explicit permissions

Identity Identification

YAT uses two-layer identity identification:

1. Transport Layer Identity: session_id / device_id
2. Business Layer Identity: actor_role / actor_session_id / actor_device_id

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Role Definitions

Publisher

Responsibility: Provide remote service

Permissions:

• ✅ Start tunnel
• ✅ Stop tunnel
• ✅ Control channels
• ✅ Modify configuration

Example Scenarios:

• Home Mac provides VNC service
• Company server provides API service
• Local development environment provides debugging service

Consumer

Responsibility: Use remote service

Permissions:

• ✅ View tunnel status
• ✅ Access remote address
• ✅ View detailed information
• ❌ Cannot start/stop tunnel
• ❌ Cannot modify configuration

Example Scenarios:

• Office computer accessing home Mac
• Mobile phone accessing company server
• Customer accessing demo environment

Controller

Responsibility: Manage tunnel configuration (reserved role)

Permissions:

• ✅ All Publisher permissions
• ✅ Manage sharing settings
• ✅ Manage participants

⚠️ Note: Controller role is currently reserved, not yet implemented.

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Multi-Device Collaboration

Typical Scenarios

Scenario 1: Remote Work

Home Mac (Publisher)
  ↓ Create tunnel, share
  ↓
Office Laptop (Consumer)
  ↓ Access shared tunnel
  ↓
Remote desktop connection successful

Configuration Steps:

1. Home Mac:

   • Create ARD tunnel
   • Set to Shared mode
   • Role auto-set to Publisher
   • Start tunnel

2. Office Laptop:

   • Login to same account
   • See shared tunnel in tunnel list
   • Role auto-set to Consumer
   • Click to connect remote desktop

Scenario 2: Team Collaboration

Developer A (Publisher)
  ↓ Create API tunnel
  ↓
Developer B (Consumer)
  ↓ Access API
  ↓
Tester C (Consumer)
  ↓ Access API

Role Assignment Rules

Assignment at Creation

• Creator device: Default Publisher
• Other devices: Auto Consumer

Runtime Resolution

YAT resolves roles from following sources:

1. Participants list - Runtime participant information
2. Sessions list - Session information
3. Config configuration - tunnelRole field

// Role resolution priority
1. role in participants
2. publisherDeviceId / consumerDeviceId in sessions
3. config.tunnelRole
4. Default fallback

Permission Matrix

Operation	Publisher	Consumer	Controller
Start Tunnel	✅	❌	✅
Stop Tunnel	✅	❌	✅
View Status	✅	✅	✅
Access Service	✅	✅	✅
Modify Configuration	✅	❌	✅
Delete Tunnel	✅	❌	✅
Manage Participants	❌	❌	✅

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Session Management

What is Session?

Session represents one tunnel running instance.

Session ID Format

Format: {appId}:{tunnelId}:{deviceId}:{actorRole}

Examples: 
- app-ard:tunnel-123:device-abc:publisher
- app-ard:tunnel-123:device-xyz:consumer

Why Need Role Suffix?

Same device may play different roles at different times:

Device A morning: publisher (service provider role)
Device A afternoon: consumer (accessing other services role)

Session distinction:
- ard:tunnel-123:device-A:publisher
- ard:tunnel-456:device-A:consumer

Session Lifecycle

Create tunnel
  ↓
Start channels → Create Session
  ↓
Running → Session active
  ↓
Stop channels → Session ended
  ↓
Delete tunnel → Session cleaned

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Device Management

Device ID

Each device has a unique device ID:

Format: device-{random-string}
Example: device-a1b2c3d4e5f6

View Device Information

In tunnel details' Participants section, you can see:

• Device ID
• Role
• Status (Online/Offline)
• Last Online Time

📸 [Screenshot Location] Participants List

Description: Shows device ID, role labels, status indicators

Device Status

Status	Description
Online	Device online, participating in tunnel
Offline	Device offline
Idle	Device online but not participating

Manage Devices

Remove Device (In Development)

Future version support:

1. Enter tunnel details
2. Find participants list
3. Click Remove button
4. Confirm remove

⚠️ Note: Removing Publisher device will cause tunnel to stop

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FAQ

Q: How to switch roles?

Currently does not support runtime role switching.

Solution:

1. Stop tunnel
2. Delete tunnel
3. Recreate on new device

Q: Can one device have multiple roles?

Yes. Same device can play different roles in different tunnels:

Tunnel A: Publisher
Tunnel B: Consumer

But in same tunnel, one device can only have one role.

Q: What happens when Publisher goes offline?

Tunnel will stop. Because Publisher is service provider, service unavailable when offline.

Q: Can Consumer become Publisher?

Currently does not support dynamic conversion.

Design reason:

• Publisher needs to provide local service
• Consumer only accesses service
• Role conversion requires service migration

Q: How to view current device ID?

In developer tools console:

localStorage.getItem('device:id')

Q: Can device ID be modified?

Not recommended. Device ID is used for:

• Identity identification
• Session management
• Permission control

Modification may cause:

• Confused tunnel state
• Permission loss
• Session failure

Q: Will multi-device simultaneous operations conflict?

YAT uses revision-based conflict resolution mechanism:

1. Increment revision on each modification
2. Sync latest state on conflict
3. 409 conflict → sync → retry

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💡 Best Practices

1. Clear Role Division

• Publisher: Stable server device
• Consumer: Mobile client device

2. Reasonable Sharing Mode Settings

Personal multi-device: Shared
Team collaboration: Shared
Sensitive service: Exclusive

3. Monitor Device Status

Regularly check participants list:

• Is Publisher online
• Is Consumer count reasonable
• Any abnormal devices

4. Device Naming Convention

Recommend labeling on devices:

MacBook-Pro (Publisher)
ThinkPad (Consumer)
iPhone (Consumer)

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📚 Related Documentation

• Tunnel Management - Create shared tunnels
• Apps and Extensions - ARD multi-device usage
• FAQ - Role-related issues

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YAT Team - Making intranet penetration simpler