Bukkit

Basically, when the configuration is set Open:true, it bypasses all functions. EnableLogins: true enables players to login. Now if ingamelogin is set to false then the plugin will look to see if the player is registered and permits the user to full access. If enablelogins: false is set then only registered players will be allowed to access the server, now with futher security you can have ingamelogins: true to further secure your server and force players to be registered and login to the server. However all registered players will have full access.