Joomla Plugin: Alarm System

Joomla_Alarm_System

 

I would like to recommend Joomla plugin named Alarm System which added extra protection to Joomla Administrator/backend access.

Joomla_Alarm_System

With this plugin, you could enable the Alarm based PIN before access to your Joomla application. 

Feel free to install Joomla Alarm System as URL below as it is free to use.
http://extensions.joomla.org/extensions/access-a-security/site-security/login-protection/25162