Method, system, mobile device, apparatus and computer program product for validating rights objects
A method, system, mobile device, apparatus and computer program product are provided for accurately determining whether one or more rights objects associated with a mobile device are valid. In particular, a secure time source (e.g., DRM clock or time) may be maintained by the mobile device and used to check the validity of the one or more rights objects. In order to ensure that the secure time source or clock remains accurate, the mobile device may update the secure time source by regularly requesting and receiving the DVB-H network time from a DVB-H network entity. Because the DVB-H network time is secure, accurate and readily accessible, it provides an ideal tool for correcting possible drift in the mobile device's secure time source.
1. A method of determining whether one or more rights objects associated with a mobile device are valid, said method comprising:
retrieving a DVB-H (Digital Video Broadcast-Handheld) network time;
updating a secure clock maintained on the mobile device based at least in part on the DVB-H network time and a user-set clock, wherein the secure clock is not user-changeable, updating the secure clock comprising:
determining a difference between the DVB-H network time and the user-set clock,
storing the difference, and
calculating the secure clock based at least on the stored difference,
re-retrieving the DVB-H network time every predetermined interval of time,
at each interval, re-calculating a new difference between the DVB-H network time and the user-set clock,
replacing the stored difference with the new difference when the new difference differs from the stored difference, and
re-calculating the secure clock based on the new stored difference; and
using the secure clock to determine whether one or more rights objects associated with the mobile device are valid.
2. The method of claim 1 , wherein a time period during with the one or more rights objects is valid is checked using the secure clock.
3. The method of claim 1 , wherein retrieving the DVB-H network time comprises automatically requesting the DVB-H network time from a DVB-H network entity upon boot up of the mobile device.
4. The method of claim 1 , wherein retrieving a DVB-H (Digital Video Broadcast-Handheld) network time comprises:
requesting the DVB-H network time from a DVB-H network entity.
5. The method of claim 4 , further comprising:
in response to receiving an error message indicating that the mobile device is outside of a DVB-H signal coverage area, re-sending the request to the DVB-H network entity for the DVB-H network time.
6. The method of claim 5 , wherein the re-sending the request is done for a predetermined number of times.
7. The method of claim 6 , wherein the re-sending the request is done until the DVB-H network time is retrieved.