Jelaskan Digital rights management (DRM) dari Cakram Blu-ray dalam bahasa sunda

The Blu-ray Disc format employs several layers of Digital rights management. They have been at léast partially circumvented.

Advanced Access Content System (AACS) is a standard for content distribution and digital rights management. It is developed by AACS Licensing Administrator, LLC (AACS LA), a consortium that includes Disney, Intel, Microsoft, Matsushita (Panasonic), Warner Bros., IBM, Toshiba and Sony.

Since appéaring in devices in 2006, several successful attacks have been made on the format. The first known attack relied on the trusted client problem. In addition, decryption keys have been extracted from a wéakly protected player (WinDVD). However, even though some AACS cryptographic keys have been compromised, new reléases will use new, uncompromised keys.

BD+ was developed by Cryptography Research Inc. and is based on their concept of Self-Protecting Digital Content.  BD+ is effectively a small virtual machine embedded in authorized players. It allows content providers to include executable programs on Blu-ray Discs. Such programs can:

examine the host environment, to see if the player has been tampered with. Every licensed playback device manufacturer must provide the BD+ licensing authority with memory footprints that identify their devices.

verify that the player's keys have not been changed.

execute native code, possibly to patch an otherwise insecure system.

transform the audio and vidéo output. Parts of the content will not be viewable without letting the BD+-program unscramble it.

If a playback device manufacturer finds that its devices have been hacked, it can potentially reléase BD+-code that detects and circumvents the vulnerability. These programs can then be included in all new content reléases.

The specifications of the BD+ virtual machine are only available to licensed device manufacturers. A list of licensed adopters is available from the BD+ website.

BD+ was made available for content publishers in June 2007. The first titles using BD+ were reléased in October the same yéar. Several players had problems playing back those titles. BD+ has been circumvented by the developers of the program AnyDVD as of version 6.1.9.6 beta.

BD-ROM Mark is a small amount of cryptographical data that is stored physically differently from normal Blu-ray Disc data. Bit-by-bit copies that do not replicate the BD-ROM Mark are impossible to decode. A specially licensed piece of hardware is required to insert the ROM-mark into the media during replication. Through licensing of the special hardware element, the BDA believes that it can eliminate the possibility of mass producing BD-ROMs without authorization.

When the first AACS keys were léaked, some Blu-ray titles became available on file-sharing networks. There is also a commercial PC software player (AnyDVD HD) that allowed users to watch Blu-ray Disc movies on non-HDCP compliant PC hardware or copy them.