QuickTime 4 Reference

Scope of Access Keys

The scope of an access key is determined when it is registered. If a key is registered as a system access key, data protected by that key is available to any QuickTime client on the computer. If a key is registered as an application access key, data protected by the key is available only to QuickTime clients of the application that registers the key. For example, if a single access key is used to encrypt all the data on a CD-ROM, and the CD-ROM title registers the key as an application access key, the data on the CD-ROM is available only to the title and inaccessible to all other applications. This prevents users from browsing through data on the CD-ROM that is meant to remain hidden.

Access keys entered in the QuickTime control panel are always registered as system access keys.