Identifier tag to track layers in a multi-layer optical disc

Abstract

Method and apparatus for tracking layers in a multi-layer optical disc. The disc includes a first layer which stores a first set of user data and a table of contents (TOC) for the disc. A second layer stores a second set of user data and an identifier tag which identifies the second layer as corresponding to the first layer. The identifier tag can comprise a portion of, or a complete copy of the TOC, or can comprise a reference value which, among other things, identifies a revision level of the second layer. Preferably, the first layer is also provided with a reference value. In this way, a database or other mechanism can be used to track the history of the various layers of the disc. Stampers form the respective layers and the ID tags further serve to ensure correspondence thereof in the formation of the disc.

Dependencies are inferred from the claim text.