["System Structure"]
# System Structure
ArOZ Online System is designed with Modular Designs. The system is built with a list of core modules or scripts that deliver the system core services. The modules and its functions are listed below

<table class="ts table">
<thead>
<tr>
<th>Module Name</th>
<th>Functions</th>
</tr>
</thead>
<tbody>
<tr>
<td>auth.php / login.php</td>
<td>Provide authentication functions</td>
</tr>
<tr>
<td>function_bar.php / function_bar.js</td>
<td>Provide floatWindow  control API</td>
</tr>
<tr>
<td>./SystemAOB</td>
<td>Provide core system functions, including file system bridging, hardware management functions and clustering services scripts</td>
</tr>
<tr>
<td>./script</td>
<td>Provide core system scripts for front ends</td>
</tr>
<tr>
<td>./Desktop</td>
<td>Provide desktop environment to users for general purpose tasks</td>
</tr>
<tr>
<td>./msb</td>
<td>Multiple System Booting Interface config files. Allow multiple instances of ArOZ Online running on the same host.</td>
</tr>
<tr>
<td>./*</td>
<td>Other WebApp modules that runs on ArOZ Online System.</td>
</tr>
</tbody>
</table>

Scripts located in a folder called “WebApp Modules”. Each of them perform an independent task or act like a microservice that power the whole system. Users can install the WebApp modules they need using Package Manager or Upload Tools, similar to Play Store or Apple Store on current smartphones, package installed can also be uninstalled via the Package Manager with an easy of pressing a button.

ArOZ Online is built on top of multiple layers of microservices which make up the “core” of the whole system. The main components of the ArOZ Online Cloud System Architecture is as follows.

- AOauth (including auth.php / login.php etc) + user Isolation (/functions/user/userIsolation.php)
- SystemAOB (AOB stands for ArOZ Online Base), some functions include: AOR/SystemAOB/functions/
- Cluster Controller (./cluster)
- File System Bridge (./file_system)
- General Purpose Input Output Controller (./GPIO) 
- System Information (./info)
- WebApp List Menu (./list_menu)
- Package Manager (non-official, ./package_manager)
- Personalization Settings (./personalization)
- Power Management (./power)
- Windows SMB File Share Configs (./samba_config)
- System Management Tools (./system_management)
- System Statistics (./system_statistic)
- Timezone Settings (./system_time and ./timezone)
- User Isolation System (./user)
- WiFi Management Tools (./wifi)
- Upload Manager 

Here is a quick visualization of all the sub-system under the ArOZ Online System

![](img/7/0.png)

All the functions listed above are included in the ArOZ Online Barebone. This can be used to power IoT devices hub, remote 3D printer server etc.