×

Methods and apparatus for secure and adaptive delivery of multimedia content

  • US 7,313,236 B2
  • Filed: 04/09/2003
  • Issued: 12/25/2007
  • Est. Priority Date: 04/09/2003
  • Status: Active Grant
First Claim
Patent Images

1. A method of processing content for delivery in an information system, wherein the content is representable as access units, the method comprising the steps of:

  • obtaining a set of alternate versions of an access unit for a current time slot associated with the content; and

    assigning an encryption index to each access unit in the set of alternate versions of the access unit in the current time slot such that an encryption index increases over time;

    wherein each alternate version of the access unit uses a different encryption key;

    wherein the assigning step further comprises the steps of;

    obtaining an encryption index of each access unit from a set of alternate versions of an access unit of a previous time slot;

    computing sums by adding corresponding access unit lengths to each index; and

    setting the encryption index of each access unit in the current time slot equal to or greater than the maximum of the computed sums.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×