Payment Plugin: Authorize.Net CIM Integration
The biggest advantage of this plugin is that altough credit card info is entered on your website, it will be stored on Auth.Net secure servers so recurring billing is secure and you do not have to store cc info on your own website.
You need to enable CIM service in your authorize.net account to use this plugin. (Tools -> Customer Information Manager -> Sign Up Now)
This is a paid service.
Enable and configure plugin in aMember CP -> Setup -> Plugins
You NEED to use external cron for this plugin.