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How to configure port forwarding in AirOS

Author: Skyhook 28 February 2009
Contents: How to configure port forwarding in AirOS
Remark: Tested on AirOS version 3.3.1 (applicable for Router mode)
Edited by:stagecoach 28 September 2009
Remark: Tested on AirOS 3.4

Introduction

Port Forwarding allows specific TCP/ UDP ports to be forwarded from an external network through a NAT-ed router to hosts located on an internal network. This is useful for number of applications such as FTP/ HTTP/ SSH servers, gaming, etc. Latest AirOS Versions support PortFW, for detailed info see AirOS Router Mode

First some conceptual definitions:

Router-mode and NAT enabled	AP/ AP-WDS	STA/ STA-WDS
LAN interface	external network	internal network
WLAN interface	internal network	external network

Consider the simple diagram below. We want to access some server application on the Internal/ Wireless Network from the External Network. To achieve this, we need to forward ports from the External Network to the AirOS WLAN/ Internal Network.

AirOS Device is configured as Access Point/ WDS-AP in Router Mode, with WLAN IP Address 192.168.0.0/24 and LAN IP Address 10.10.10.0/24.

Configuring

Login into AirOS WEB User Interface, go to NETWORK Tab and set as below:

• Network Mode: Router
• Enable NAT: check box on
• Port Forwarding: check box on (to activate Configure... button)
  
  Note: Port Forwarding are located in WLAN Network Settings if the device is running in AP/AP-WDS mode or in LAN Network Settings if the device is running in Station/Station-WDS
• Press Configure... button to open Port Forwarding window
• Add a new rule setting:
  
  • Private IP: 10.10.10.30 (Windows PC address)
  • Private Port: 3389 (port on Windows PC)
  • Type: TCP
  • Public Port: 3389 (port on AirOS Device)
  • Comment: RemoteDesk (or any your comment...)
  • Enabled: check box on
• Click Save button to confirm
• Click Apply button to apply changes
• Wait until process is complete

Now you should be able to connect to Windows PC via Remote Desktop typing 192.168.1.20 on Remote Desktop Client.

Note: you can reach internal WEB Server, FTP Server, SSH login to servers, etc simply replicating a Port Forwarding rule for each services.