Generally, non-persistent licenses are used for immediate playback of content and can also be thought of as “in-memory” licenses. Non-persistent licenses are intended to last for only as long as the current consumption session, or a single playback. Persistent licenses can be stored in non-volatile memory on a client device after they are received and are used for any playback session until time-based rights restriction embedded in the license is reached. For example, a persistent license can be used to play back downloaded content while the device is offline. Enforcing protection mechanisms in these scenarios require a local trusted reference for time. Both persistent and non-persistent licenses include a range of rights and restrictions set by the content licensor.