Which is the simplest way to export attachments ?

[setecastronomy]

I have to make visible selected attachments in articles to another application. Certainly the agent can download them and save on his computer and then upload to the other application but it is a tedious work.
Other ideas I had:
1- use the download link and let the other application to download the attachment. Unfortunately it is not as simple as issuing an HTTP get because you need to be authenticated in order to perform the request. So it is a bit more complicated than expected. Don't now if I can create an IP white list (the server of the other application) with a default user, otherwise the other application needs to authenticate and only after that can ask the attachment.
2- I can configure OTRS to put the attachment on the filesystem and then share it via NFS. The other application can find the right directory using the article id and the corresponding path (taken from the article table on DB), but I found no way to retrieve the file name. I can list the directory and take the first, second, third name etc. but I think there is a better way.

What would you suggest ?

Thanks
Filippo