How can user(external) upload some specific document(media-file ex- PDF file) to CD server?
Below point need to take care: Uploaded media files should not be overridden once publishing is done.So media files must be also maintain onto CM(master db). Here also CM user can manage uploaded files.
Here we are using 3 CD server(load-balancing) and 1 CM server.
Sitecore 8.2 update 3.