A PHP script with x-accel-redirect is the best way to implement this -
one internal script to generate content keys, and another to decode
and serve content (handling key verification, time-based expiration,
download counting and download-count based expiration, etc.) via
x-accel-redirect. Download counters are best handled using memcached.

Cheers
Kon

On Mon, Jun 15, 2009 at 3:10 AM, XUFENG<xufengnju@sina.com> wrote:
> We can add one parameter as the 'salt' to encryt what will appear in the key=?? part,not in plain text.