TP-LINK TD-W8961N - How to Backup and Restore modem configuration

Mediaket shows you how to Backup and Restore TP-LINK TD-W8961N modem configuration  in less than 3 minutes.
Why you need to backup your modem router configuration? ...

"The Backup Settings option allows you to save a file containing all your modem router's configuration settings, like wireless settings, port forwarding, WAN setup, DNS, All passwords, wireless shared key etc. to a file on your computer. This file can then be used to restore your settings if the router is reset to the Factory Default settings."

300Mbps Wireless N ADSL2+ Modem Router:

All-in-One Device: ADSL2+ Modem, NAT Router, 4-Port Switch and Wireless N Access Point.
Wireless N speed up to 300Mbps makes it ideal for heavy bandwidth consuming or interruption sensitive applications like online gaming, Internet calls and even the HD video streaming.
Easy Setup Assistant with multi-language support provides quick & hassle-free installation.
Easy one-touch wireless security encryption with the ‘WPS’ button and easy Wi-Fi On/Off button.