There is an alphabet soup of terms and acronyms people use when talking about content protection technologies. Some of those that are more commonly used are described here:
Advanced Access Content System (AACS)
AACS is a standard for content distribution and protection for the next generation of optical discs and DVDs. The specification was publicly released in 2005 and the standard has been adopted for HD DVD and Blu-ray Disc. AACS uses the Advanced Encryption Standard (AES) to protect media content. It was developed by the AACS Licensing Administrator (AACS LA), a consortium that includes Disney, Intel, Microsoft, Matsushita (Panasonic), Warner Brothers, IBM, Toshiba and Sony.
Advanced Encryption Standard (AES)
AES is an encryption standard that is endorsed by the National Institute of Standards and Technology in the United States. Many Digital Rights Management (DRM) applications use the secure 128-bit AES in their architecture.
Analog Hole
Analog hole describes the vulnerability in a digital content protection system that arises from converting digital content to analog, copying it, and then re-converting it to a digital format with copy protection removed. This vulnerability exists because all digital content needs to be converted to analog in order to be perceived by human senses.
Blu-ray Disc (BD)
BD is a popular format (the other is HD DVD) for the next generation of high-density optical discs that were designed for high-definition video and data storage. It was developed by the Blu-ray Disc Association, a grouping of several key device manufacturers and content producers.
Broadcast Flag
A Broadcast Flag is a signal (or “flag”) that is embedded in the data stream of digital television content. This flag indicates whether restrictions are applicable to that content. Common restrictions include the inability to save the content onto recordable media such as hard disks, limitations as to making secondary copies and restrictions that limit copying to only analog devices.
Conditional Access (CA)
CA is a term used to describe a system of controls over the viewing of television, particularly digital television. It protects content by requiring certain criteria to be met before access is granted. CA is typically used in the broadcast of digital television where content is scrambled and access is provided only to those with valid decryption smart cards.
Content Protection for Recordable Media and Pre-Recorded Media (CPRM/CPPM)
CPRM/CPPM is a method that uses encryption for controlling the copying, moving and deletion of digital content when recorded on physical media. The types of physical media supported include recordable DVD media and flash memory. It is widely deployed in the popular Secure Digital (SD) card flash memory format. It was developed by the 4C Entity consortium which includes IBM, Intel, Matsushita and Toshiba.
Content Scrambling System (CSS)
CSS is a Digital Rights Management (DRM) system used on almost all commercially produced DVD Video discs. It utilizes a proprietary system of encryption that requires DVD players to be authenticated before DVD data can be read. Using a simpler 40-bit system of encryption, CSS has been superseded by AACS which uses the more sophisticated 128-bit AES encryption for the next generation of optic media such as HD-DVD and Blu-ray Disc.
Copy Protection, Copy Prevention or Copy Restriction
Copy protection is a term that refers to technological methods for preventing the unauthorized reproduction of copyrighted video, audio, software and other media. Examples of copy protection technology include encryption systems such as CSS and AACS. Digital Millennium Copyright Act (DMCA)
The DMCA is copyright law enacted in the United States in 1998. It prohibits the circumvention of Digital Rights Management (DRM) access controls and the production of devices or services that are used for such circumvention. It also addresses copyright protection on the internet.
Digital Rights Management (DRM)
DRM is a set of tools used to manage copyright for digital content. The underlying goal of DRM is to transform the digital marketplace into a legitimate one, which offers security and safeguards for the owners of content, as well as appeal and flexibility for consumers. DRM can include tools such as encryption but it can also include others such as databases of information about works under copyright and information embedded within content to indicate who the copyright holder is.
Digital Television (DTV)
DTV is a system for broadcasting and receiving video content through digital signals, as opposed to analog signals which are used by traditional analog television systems. DTV is more efficient than analog television in its use of radio-frequency spectrum. It also allows High-definition television (HDTV) to be transmitted and received.
Digital Transmission Content Protection (DTCP)
DTCP is a DRM technology that uses encryption to protect digital motion pictures, television programs and audio against unauthorized interception and copying when transmitted through wired or wireless “digital home” systems (e.g., between a digital set-top box and digital video recorder, or between a personal computer and a digital TV). DTCP technology gives copyright owners the security needed to promote the release of more digital content, which can be transmitted digitally throughout the home. DTCP is also referred to as “5C” content protection, a reference to the five companies who created DTCP: Hitachi, Intel, Matsushita, Sony, and Toshiba.
Encryption
Encryption is the process of using an algorithm or “cipher” to render information unreadable to everyone except those possessing a “key” that allows the encrypted information to be decrypted.
Fair Dealing
A similar term used in some common-law influenced countries for what is termed as fair use in the United States.
Fair Use
Fair Use is a principle of copyright law in the United States that allows the reproduction of copyrighted material without requiring permission from the rights holders under specific circumstances. Examples may include quoting a book in a review, or making a copy of an audio recording exclusively for personal domestic use.
Fingerprinting
Fingerprinting is a set of techniques for analyzing content, reducing its unique characteristics to a set of one or more identifiers that serve as “fingerprints,” and looking those fingerprints up in a database to determine the identity of the content. Fingerprinting is passive as the identification and tracking of content does not interfere with a user’s ability to play, copy, or send it. It typically complements active content control techniques such as encryption. Recent fingerprinting solutions have focused on dealing with video and audio content uploaded onto the World Wide Web. When new files are uploaded to a website a fingerprinting system checks the database for matches. Copyrighted material can then be blocked or posted, depending on whether it is licensed for use on the website.
High-bandwidth Digital Content Protection (HDCP)
HDCP is a proprietary form of DRM that was developed to protect digital audio and video content transmitted across Digital Visual Interface (DVI) and High-Definition Multimedia Interface (HDMI) connections. HD DVD, Blu-ray Disc and DVD players with DVI or HDMI connectors use HDCP to establish an encrypted digital connection. High-definition digital video content transmitted to a non-HDCP compliant television may be restricted to DVD or lower quality, or may not be displayed at all.
High Definition DVD or HD DVD
HD DVD is a popular format (the other is Blu-ray Disc) for the next generation of high-density optical discs that were designed for high-definition video and data storage. Developed by the DVD Forum, HD DVD technology is derived from standard DVD technology.
High-definition Television (HDTV)
HDTV is a DTV system that is designed to provide viewers with programming that is much higher in resolution than what is available through traditional television systems.
Peer-to-Peer (P2P)
P2P is a term used to describe a computer network that uses the connections between its participants (or peers) to share and deliver data. Such networks differ from traditional networks where resources are centralized in a small number of servers. P2P networks are used in a wide variety of applications including the sharing of video, audio or data as well as in Internet Protocol (IP) telephony.
Place or Space Shifting
Space shifting is the moving of digital content, such as an MP3 song, from one device to another, such as from a PC to a portable MP3 player. This may involve permitted copying operations. However, it can also be used for fraudulent redistribution, which necessitates some form of copy protection. Place-shifting refers to moving of television signals over IP to remote locations. (also called remote access).
Protected Media Path (PMP)
Microsoft’s Windows Vista contains a DRM system called the PMP which stops DRM- protected content from playing while unsigned software is running. This prevents unsigned software from accessing the content. Additionally, PMP can also encrypt information during transmission to the monitor or the graphics card, making it difficult to make unauthorized recordings.
Rights Management Information (RMI)
RMI means information which identifies the content, the author of the content, the owner of any rights in the content, or information about the terms and conditions of use of the content. Such information can be embedded in the content itself or appear in connection with the dissemination of the content. In some definitions, RMI can also refer to information about how that content has been used. For example, RMI could include the number of times that a song has been listened to.
Set-Top Box (STB) or Set-Top Unit (STU)
A set-top box is a device that acts as an interface between a television set and an input signal, turning that signal into video that can be displayed on the screen. Set-top boxes are commonly used as means to unscramble pay-TV channels and as a tool for copy protection, for example, as part of a Conditional Access (CA) system.
Streaming media
Streaming media refers to multimedia content that is delivered in a constant stream over a communications network such as the internet. Such content is typically displayed to the end-user while it is being delivered by the provider. Some streaming providers use DRM technologies, such as encryption, to prevent the unauthorized reproduction of the streamed content.
Technological Protection Measures (TPM)
TPM refers to a range of technologies used to protect digital content. It can refer to technologies that employ encryption, watermarking or fingerprinting and other techniques.
Time Shifting
Time shifting involves watching or listening to media programming at a time other than when it was originally broadcast. Recording or copying a TV program on a personal video recorder for later watching is the most common example. While some time shifting operations may be permitted from a content protection point of view, such copying may also be used for fraudulent redistribution, necessitating the introduction of copy protection.
Trusted Platform Module (TPM)
TPM is an add-in security hardware component for PCs. It includes security features designed to improve security as well as copy protection. Such features can include digital signatures, random number generation, and protected storage.
Video Content Protection System (VCPS)
VCPS is an anti-copy technology that prevents DVD recorders from recording broadcast television programs if a Broadcast Flag prohibits it.
Watermarks or Digital Watermarks
Watermarking is a technique that allows certain data to be embedded into visible content such as digital images, audio or video in a way that makes such data imperceptible and difficult to remove. The data embedded in a watermark is often the identity of the content, though it could also include copyright-related information such as the identity of a user or device that downloaded it, or of a retailer that sold it, as well as other verification messages.
