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Information about Content Scramble System

Content Scramble System (CSS) is a Digital Rights Management (DRM) scheme used on almost all commercially produced DVD-Video discs. It utilizes a weak, proprietary 40-bit stream cipher algorithm. The system was introduced around 1996 and has subsequently been compromised.

The CSS key sets are licensed to manufacturers who incorporate them into products such as DVD drives, DVD players and DVD movie releases. Most DVD players are equipped with a CSS Decryption module. CSS key is a collective term for authentication key, disc key, player key, title key, second disk key set, and/or encrypted key.

In October 1999, Jon Lech Johansen and two people who remained anonymous reverse engineered the algorithm and DeCSS was released. The CSS algorithm was soon revealed to be easily susceptible to a brute force attack. The weakness of the protection is due to US government crypto-export regulations, apart from being an example of the trusted client problem. The CSS algorithm has been superseded by the Cryptomeria cipher in newer DRM schemes such as CPRM/CPPM, or by AES in the AACS copy-protection schemed used by HD DVD and Blu-ray Disc.

Specification

Authentication is a process for a DVD drive and CSS Decryption module to recognize (or authenticate) each other. It is necessary before reading data from DVDs. Authentication keys are used for this process.

Title keys are used for scrambling and descrambling actual data on DVDs called titles. A title could be a complete motion picture, a trailer or similar self-contained unit.

Disc keys are used for decrypting title keys on DVDs.

Player keys are used for decrypting disc keys on DVDs. Each DVD player manufacturer is allocated one of approximately 400 player keys to incorporate in its players.

While most CSS decrypting software is used to play DVD films, other non-playing software (such as DVD Decrypter, AnyDVD, DVD43, Smartripper and DVD Shrink) allows a region-specific DVD to be copied as an all-region DVD. Such software is also able to remove Macrovision, Content Scrambling System (CSS), region codes, and disabled user operations (UOPs).

See also

References

Digital rights management (DRM) is an umbrella term that refers to access control technologies used by publishers and other copyright holders to limit usage of digital media or devices.
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DVD

Media type: Optical disc
Capacity: 4.7 GB (single layer), 8.5 GB (dual layer)
Usage: Data storage, audio, video, games

Optical disc authoring
  • Optical disc
  • Optical disc image
  • Recorder hardware
  • Authoring software

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The word "proprietary" indicates that a party, or proprietor, exercises private ownership, control or use over an item of property, usually to the exclusion of other parties.
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40-bit encryption refers to a key size of forty bits, or five bytes, for symmetric encryption; this represents a relatively low level of security. A forty bit length corresponds to a total of possible keys.
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stream cipher is a symmetric cipher where plaintext bits are combined with a pseudorandom cipher bit stream (keystream), typically by an exclusive-or (xor) operation. In a stream cipher the plaintext digits are encrypted one at a time, and in which the transformation of successive
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DVD

Media type: Optical disc
Capacity: 4.7 GB (single layer), 8.5 GB (dual layer)
Usage: Data storage, audio, video, games

Optical disc authoring
  • Optical disc
  • Optical disc image
  • Recorder hardware
  • Authoring software

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DVD player is a device that plays discs produced under both the DVD Video and DVD Audio technical standards, two different and incompatible standards.

Most hardware DVD players
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Jon Lech Johansen (born November 18, 1983 in Harstad, Norway), also known as DVD Jon, is a Norwegian (his father is Norwegian and mother is Polish) who is famous for his work on reverse engineering data formats.
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Reverse engineering (RE) is the process of discovering the technological principles of a device or object or system through analysis of its structure, function and operation. It often involves taking something (e.g.
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DeCSS is a computer program capable of decrypting content on a DVD video disc encrypted using the Content-Scrambling System (CSS).

Origins and history

DeCSS was devised by three people, two of whom remain anonymous.
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brute force attack is a method of defeating a cryptographic scheme by trying a large number of possibilities; for example, exhaustively working through all possible keys in order to decrypt a message.
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In computing, a trusted client is a device or program controlled by the user of a service, but with restrictions designed to prevent its use in ways not authorised by the provider of the service.
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Cryptomeria cipher
The Feistel function of the Cryptomeria cipher algorithm.

General
4C Entity
2003

DES

CSS

Cipher detail
Key size(s):| 56 bits

Block size(s):| 64 bits
Feistel network
10

The
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Content Protection for Recordable Media and Pre-Recorded Media (CPRM/CPPM) is a mechanism for controlling the copying, moving and deletion of digital media on a host device, such as a personal computer, or other digital player.
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Content Protection for Recordable Media and Pre-Recorded Media (CPRM/CPPM) is a mechanism for controlling the copying, moving and deletion of digital media on a host device, such as a personal computer, or other digital player.
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AES may refer to:

Standards, systems, and methods
  • The Advanced Encryption Standard in cryptography
  • Advanced Encryption Standard process, in cryptography, the process of choosing an algorithm for standardization as AES

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The Advanced Access Content System (AACS) is a standard for content distribution and digital rights management, intended to restrict access to and copying of the next generation of optical discs and DVDs.
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HD DVD

Media type: High-density optical disc
Encoding: VC-1, H.264, and MPEG-2
Capacity: 15 GB (single layer) 30 GB (dual layer)
Read mechanism: 1x@36 Mbit/s & 2x@72 Mbit/s
Developed by: DVD Forum
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Blu-ray Disc

Media type: High-density optical disc
Encoding: MPEG-2, MPEG-4 AVC (H.264), and VC-1
Capacity: 25 GB (single layer), 50 GB (dual layer)
Read mechanism: 1x@36 Mbit/s & 2x@72 Mbit/s
Developed by: Blu-ray Disc Association
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DVD

Media type: Optical disc
Capacity: 4.7 GB (single layer), 8.5 GB (dual layer)
Usage: Data storage, audio, video, games

Optical disc authoring
  • Optical disc
  • Optical disc image
  • Recorder hardware
  • Authoring software

..... Click the link for more information.
DVD

Media type: Optical disc
Capacity: 4.7 GB (single layer), 8.5 GB (dual layer)
Usage: Data storage, audio, video, games

Optical disc authoring
  • Optical disc
  • Optical disc image
  • Recorder hardware
  • Authoring software

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Please help Wikipedia by adding references. See the for details.
This article has been tagged since September 2007.

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AnyDVD is a Microsoft Windows driver that decrypts and removes content restriction from DVDs on-the-fly. With an upgrade, it will also do the same for HD DVD and Blu-ray. The AnyDVD program runs in the background, making discs unrestricted and region-free.
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DVD43 is a CSS encryption breaking program that works behind the scenes of DVD copying programs so that they can read and copy copy-protected DVDs.

External Links

You can download DVD43 from many sites. Some are below:
  • DVD43's Home Site
  • Free-Codecs.

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Smartripper is a freeware software application that can be used to create a copy of a DVD on a hard drive. The program supports three copy modes: Movie (copy the movie only), Files (copy selected files only) and Backup (copy whole disk).
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DVD Shrink is a freeware program for Microsoft Windows that facilitates backing up DVD movies. As store-bought DVDs are typically dual layer (8.5 GB) and normal blank DVD media are single layer (4.
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Macrovision Corporation

Public (NASDAQ:  MVSN )
Founded 1983
Headquarters Santa Clara, California, USA

Key people Fred Amoroso, President and Chief Executive Officer

Employees 800+
Website www.macrovision.
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Regional lockout is the programming practice, code, chip, or physical barrier used to prevent the playing of media designed for a device from the country where it is marketed on the version of the same device marketed in another country.
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The DVD Copy Control Association (DVD CCA) is an organization primarily responsible for the copy prevention of DVDs. The Content Scramble System (CSS) was devised for this purpose to make copyright infringement difficult.
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The Advanced Access Content System (AACS) is a standard for content distribution and digital rights management, intended to restrict access to and copying of the next generation of optical discs and DVDs.
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