CKFinder with external images not on the server

Question

My application has images hosted on shared third party external server, how to define folder of shared third party image hosting in filebrowserBrowseUrl ? I only have urls of images that are uploaded.

CKEDITOR.replace( 'editor1', {
    filebrowserBrowseUrl : 'browse.php',
});

what should be my logic in browse.php ?

Note:- I only have urls of images not the physical location or directory name.