REDIRECT protection type
This protection method may be used to protect embedded content like PDF files
or Flash movies if the LINK protection method is not an option. We strongly
recommend you to use LINK protection method for all file types when possible.
REDIRECT protection method check HTTP referrer value just like REFERER protection
but when check is passed instead of simply allowing access to the file it issues
a redirect to a temporary signed link. Then it operates like a LINK protection
method by validating a signature and timestamp. So all embedded applications
that usually don’t set HTTP referrer header uses this signed link to work.
The advantage of this method is it does not require you to edit anything on
your site unlike the LINK protection method. Simply set protection directory
and apply. Disadvantage is that it still rely on HTTP referer header in initial
request while LINK protection is free of this limitation.