Recording method, producing method, playback method, apparatus, and information recording medium

摘要

Each embodiment of the present invention uses an information recording medium comprising an area A recording key management information and a read-only area B recording compressed data comprising compressed key management information. This information recording medium can verify validity of the key management information by confirming a match between the compressed data for the key management information read from the area A and the compressed data read from the read-only area B. Accordingly, it is possible to record the key management information by preventing unauthorized rewriting even on an information recording medium with a limited read-only area size.