Need help with web.config security - Can't figure out where the security group is located in the app

Hi,
   We have sepeartate folder called Managers in one of our web apps. And there was a security build around that folder in a web config file as below
<?xml version="1.0"?>
<configuration>
    <appSettings/>
    <connectionStrings/>
    <system.web>
      <authorization>
        <allow roles="AllManagers"/>
        <deny users="*"/>
      </authorization>
    </system.web>
</configuration>
I couldn't figure out where this group located in the application. Usually all our groups are defined in Active directory but except this group. I am not sure if this is defined on the web server or some where in the app itself. Because i ...