Unless you use SSL, a user logs into Joomla sending his password in plain text across the network. A malicious user could take advantage of this vulnerability and can have access to the back-end.
This plugin is an alternative to SSL. It uses RSA to encrypt passwords or any other data you want in your component.
It is necessary to have the bcmath extension
Works with Signal Login, JTP Horizontal Login, PWC Login, Inline Login and vtj login modules.
For other Joomla extensions, like Alpha Registration, Community Builder, Core Design Login Module, Yoo Login, YJ Pop Login Module you can find plugins at http://www.ratmilwebsolutions.com/downloads/encryption-plugins.html.
No need to set up. Just install it and install the required plugins.