Unified broadcast encryption system

A processor-implemented method of performing a unified broadcast encryption and a traitor tracing for digital content, comprising:

• dividing a media key tree into subtrees, said media key tree including media keys and initial values, wherein said initial values are random values;
• dividing said digital content into a plurality of segments and converting at least some of said segments into a plurality of variations;
• transforming said initial values into media key variations;
• assigning a separate media key variant to each of said subtrees;
• storing a unified media key block including said media key tree on said media;
• decrypting said digital content by reading and processing said media key block on said media to obtain said media key variations required for each of said variations of said digital content, and by decrypting said digital content by decrypting a title key and locating a variant number from a variant key table using said media key variation, and by using said decrypted title key to decrypt and play said segments and said variations;
• transforming said initial values using a program on said media into media key variations;
• using a soft key conversion data transformation to transform said initial values into media key variations;
• tracing a traitor by identifying a variation and a subdivided subtree used by said traitor to circumvent said encrypted digital content, wherein said variation includes said variation calculated from said transformation of said initial value:
• and
• revoking a traitor using said identified variation and said identified subdivided subtree by removing said identified subdivided subtree from an associated subtree if said subdivided subtree is a leaf of said media key tree.