I have done the next : At the remote server I detect the public IP of the client and if it is at one of our offices, I set the link to load the upload pages from the local server.
At the local servers I put all the scripts (javascript & php) to upload the files. I send the full files to the local server, and the php script makes a thumbnail of the images and send throught post to the remote server. My first scenario I tried: -Select and reduce from client -Send full images to local server -Send thumbnails to remote server My second scenario I tried: -Select from client -Send full images to local server -Send thumbnails from the local server to remote server The second scenario is about 5-10% more slower (totaly 70-80 seconds for 30 MB). With the first scenario the time between the client has to wait the javacript finish to create thumbnails, that is about 50% of the time. In the second scenario only few seconds. In the first scenario, remote and local files are send at the same time, in the second, untill the local file is sent, the remote file isn't send. I finaly chosed for the second because I prefere the user machine working, and not frozen the thumbnail time. The second reason is that I insert the filename in a database and rename the file based on the ID inserted at the table, and with this method, I send the thumbnail with the ID based name instead of the original filename. It prevents remote client to upload outside of our networks, it's possible I maintain the full upload directly to remote server but it will be slow. I will try to upload the scripts
