The first thing you need to do to setup your Belkin router for VOIP with Faktortel is to login to the web interface.
To do this please do the following: Initial Steps

Open a web browser such as Mozilla Firefox

Type: http://10.1.1.1 in your web browser and press Enter ( or the GO button ).

Click on Advanced Setup.

Click on VOIP.

Click on Port Settings.

Tick / Check: Phone Line 1.

For Line 1, enter the following:

Phone Number: Your FaktorTel PHONE NUMBER, ( NOT Your FaktorTel USER ID )

Display Name: Your Name

SIP Server: sip.faktortel.com.au

Username: Your FaktorTel USER ID

Password: Your FaktorTel PASSWORD

Then Click, Save Settings.

On the following page, ( which should be the sip settings page ):

Proxy IP: sip.faktortel.com.au

Registrar IP: sip.faktortel.com.au

Then Click, Save Settings.

Leave the following page as is, and click Save Settings

Your device should now be connected to FaktorTel.

There are a few quick automated numbers you can dial to check that everything is working.
These are:
Service Time: 123
Echo Test ( Hear your own voice ): 600
Connect to FaktorTel's PBX: 900
Any Australian 1800 Number: 1800 - XXX - XXX