I'd used the @inidbi addon.

Regardless of that though, the easiest way would be to use the cronjob and generate some sort of index-file that simply tells your server what files are available.

As far as directly loading remote files in ArmA is concerned, that is only possible via an extension. You can read more on that here: http://killzonekid.com/arma-extension-url_fetch-dll-v2-0/