
60 Chapter 1 Embedded Computing
encrypted and separately distributed. A license server authenticates requests for
licenses, perhaps by checking for payment or other permissions. The license
request may be triggered automatically when the content is first requested to be
played, or the license may be requested manually.
Licenses provided by the Windows Media Rights Manager can specify a
number of conditions on use, such as expiration date, number of plays, whether
the content can be played on a Secure Digital Music Initiative-compliant player,
and whether the license can be backed up and restored.
The designers of high-performance embedded computing systems ...