Embodiments of the invention relate to digital content protection for recordable media using encryption and decryption based on device keys in the media. The invention increases the number of extended applications supported the media key blocks and facilitates the assignment of the applications to the media key blocks. One aspect of the invention concerns a method that comprises assigning a first media key block in a protected area of the media for extended applications accessing protected content, processing the first media key block with a first device key set to generate a first media key, and for each extended application, creating a second media key block in a protected area of the media. The second media key block is processed to generate a second media key. A content-accessing device processes the first and second media keys in order to access protected content.