If you want to use the Westell 7500 Port Forwarding you must follow this guide 1.) Connect to the Router you can see a tutorial about this here - How to connect to Westell 7500
2.) Go to Firewall.
3.) Go to Port Forwarding
4.) A warning message will apear : 
Any changes made in this section may affect your device’s performance and configuration. 
Do you want to proceed?
Click YES

Westell 7500 Port Forwarding

5.) A port Forwarding screen will be displayed, The Port Forwarding screen allows you to edit:


- Edit connection profiles, create new connection profiles
- Configure port forwarding services: predefined, customized, and port forwarding/port triggering services