Digital Rights Management (English:, abbreviated as DRM) is a series of access control technologies, usually used to control the use of digital content and equipment after they are sold

Digital Rights Management (English:, abbreviated as DRM ) is a series of access control technologies, usually used to control the use of digital content and equipment after they are sold. DRM is also sometimes referred to as copy protection , copy control, technological protection measures, etc., but these terms are disputed. Many digital publishing houses and software vendors use DRM, such as Amazon , AT&T , AOL , Apple Inc. , Netflix , Google , BBC , Microsoft , Sony , Valve Corporation (and its Steam ), etc.

Introduction

DRM controls the use, modification, and distribution of copyrighted works, and is applicable to multimedia content such as software, systems, music, and movies.

The use of DRM is controversial. Proponents argue that just as private property needs locks to prevent theft, intellectual property needs DRM to prevent unauthorized use, protect authorship and ensure a sustainable revenue stream. Opponents believe that DRM cannot effectively prevent copyright infringement, but will cause inconvenience to legitimate users, and may also hinder competition and innovation by large companies. In addition, once the DRM provider stops the service, the products using DRM technology may no longer be usable. DRM can also be used to restrict the legitimate rights and interests of users, including making backups, lending to libraries, using public domain works, research and study, and other reasonable uses . Both the Electronic Frontier Foundation and the Free Software Foundation believe that DRM is anticompetitive . The Free Software Foundation also recommends that the acronym DRM be interpreted as "Digital Restrictions Management" (Digital Restrictions Management), because the term " rights " is misleading.

Internationally, many countries have passed laws to prohibit bypassing DRM, and at the same time prohibit the development and dissemination of related tools, and discussion of related methods and techniques. These provisions are contained in the Digital Millennium Copyright Act in the United States and the Copyright Directive 2001/29/EC in the European Union.

history

As digital media has become ubiquitous, rights holders have begun to worry about the fate of their industries, especially in music and movies. Traditional media based on analog signals will inevitably be distorted when copied, while media files based on digital signals can be copied countless times without loss. The advent of the personal computer, along with the popularity of the Internet and file-sharing tools, has made piracy increasingly common.

In 1983, Japanese engineer Ryoichi Mori designed an early DRM system called Software Service System (SSS), and the later improved version was named superdistribution (superdistribution). SSS is based on cryptography technology and is decrypted by specialized hardware. In its design concept, instead of restricting the distribution of encrypted versions of digital products, users are encouraged to share them.

technology

Movie

DVD Forum 's content scrambling system was an early DRM system. It uses a simple encryption algorithm , and manufacturers who make DVD players must obtain authorization to implement this technology in their products before they can decrypt and play encrypted content in DVDs. The licensing terms dictate how DVD content can be played, including the format and method of the output signal, to ensure that the encryption of the video is not compromised when played on a TV.

In 1999, Jon Lech Johansen released DeCSS , a program for playing encrypted DVDs on Linux systems. At the time, there were no licensed DVD players on Linux systems, and the legality of DeCSS was disputed—the developers were embroiled in lawsuits, and the distribution key was limited by " illegal prime numbers ."

Also in 1999, Microsoft released WMDRM, which is used to implement DRM instructions contained in media files and restrict users from using media files. These DRM instructions can specify the number of times the file can be played, whether it can be backed up or forwarded. Subsequent WMDRM can restrict users to transfer files between devices, realize a subscription service in which files can no longer be played after they expire, and also implement regional restrictions .

The DRM system embedded in Windows Vista is called Protected Media Path , which includes Protected Video Path (PVP). When unsigned software is running, PVP will stop playing DRM-enabled movies to prevent unknown software from obtaining content. In addition, PVP can encrypt the information transmitted to the monitor or graphics card, making transcription more difficult.

Advanced Access Content System (AACS) is a DRM system for high-definition DVD and Blu-ray Disc. It was developed by the AACS LA consortium, whose members include Disney , Intel , Microsoft, Panasonic , Warner Bros. , IBM , Toshiba , and Sony . In December 2006, hackers posted online a key that could be used to gain unrestricted access to AACS-protected high-definition DVDs. After the keys were revoked, the hackers released more cracking keys.

television

Television providers in the United States use the CableCARD standard to control what users can watch.

In 2001, Fox established the concept of broadcast markers, which was supported by the Motion Picture Association of America and the Federal Communications Commission . According to the requirements of the broadcast flag bit, the TV needs to comply with a series of streaming media technical specifications, and judge whether the streaming media should be allowed to be recorded or not. This may hinder fair use applications such as time shifting . The broadcast marker bit was later adopted by DVB , a consortium developing a new digital television standard with members from about 35 countries, including about 250 broadcasters, manufacturers, network operators, software developers and regulatory bodies. In May 2005, the U.S. Federal Court of Appeals ruled that the FCC has no power to force the U.S. television industry to adopt broadcast markers.

The DVB-CPCM working group developed a follow-up version of the broadcast marker bit, and submitted the technical standard draft to the EU government in March 2007. Like most DRMs, CPCM is intended to give copyright owners control over how users use copyrighted works. "You don't even know ahead of time if you're going to be able to record or use a program or device in a particular way," said Ren Bucholz, an employee of the Electronic Frontier Foundation who paid to join the alliance . The official standard ETSI TS 102 825-X (X refers to the manuscript number) was released.

audio cd

Discs using DRM do not conform to the CD standard and can only be called CD-ROM media. As such, none of them are CDDA Red Book certified, nor are they CD-branded on the disc. These discs will not work with all CD players and may even crash when played on a PC running Windows.

In 2005, SONY BMG launched a new DRM technology without explicitly informing users or asking for consent during installation. In addition to this, the installed package also contains a rootkit with serious vulnerabilities . When these circumstances became public, SONY BMG initially tried to mitigate the impact of the software bug, but ended up having to recall millions of discs, and issued several patches to modify the add-on software, or at least remove it Rootkits. SONY was hit with several rounds of class action lawsuits , which ended in an out-of-court settlement, offering affected consumers either cash compensation or DRM-free music downloads.

In fact, SONY's DRM software has very limited ability to restrict copying, and it can only control playback on Windows, but it has no effect on other devices. Users can bypass restrictions even on Windows platforms. While SONY's DRM technology has serious vulnerabilities, its components can be easily bypassed by some operations, such as holding down shift when inserting a disc, or directly disabling the AutoRun function . In addition, it is completely possible to use the analog loophole to re-transcribe while playing music, directly bypassing the DRM restriction. The first two patches Sony issued to remove the software from users' computers failed.

In January 2007, EMI Records stopped publishing CDs with DRM, saying that "the benefits of using DRM outweigh the losses." After EMI, SONY BMG became the last company to abolish DRM. Since then, the four largest commercial record companies have no longer released CDs with DRM. CD.

Internet music

Many online music stores use DRM to restrict the download and playback of sold music:

• Before 2009, Apple's iTunes used the FairPlay DRM system. Apple does not allow other companies to use this DRM, so only Apple devices can play iTunes music. In May 2007, EMI began selling music in the iTunes+ format at a higher price, offering better sound quality (256 kbps) and without the use of DRM. In October 2007, the price of iTunes+ music dropped to $0.99. In April 2009, all iTunes music dropped DRM.

• Napster Music offers a subscription-based approach to DRM perpetual purchase. Users who subscribe to the service can download and convert unlimited music to WMA format. But once the subscription period expires, all downloaded music will not be playable until a new payment is made. Napster also charges users who want to stream music on their mobile devices $5 a month. In addition, Napster also provides users with an option to pay an additional $0.99 per song to burn it on CD. Music purchased from Napster can be played on players bearing the Microsoft PlaysForSure logo. In June 2009, Napster launched DRM-enabled MP3 music on iPhones and iPods.

• Another music download store, Walmart Music Download, charges $0.94 per track download. All music downloaded from Walmart can be played on players with the Windows PlaysForSure logo. It can be played on a Sansa MP3 player such as SanDisk , but the music must first be copied to the player's internal memory . It cannot play music directly from the SD card slot, which can be a nuisance for those experienced with MP3 players.

• The online music download service operated by SONY is called Connect, which uses SONY's OpenMG DRM technology. Music downloaded from here can only be played on Windows and SONY machines.

• Kazaa is one of the few fee-based services that offers a pricing model. However, music downloaded from Kazaa's website is DRM-protected and can only be played on computers and mobile devices running Windows Media Player and must be subscribed to on Kazaa on an ongoing basis.

Although these services use the same DRM system, they cannot be used together at present. Almost all require clients, and some require plugins .

Although DRM is very common in online music, online music stores like eMusic, Dogmazic, Amazon , Beatport , etc. do not use DRM and encourage people to share music. Other online sellers, such as Xiie.net, only sell music from lesser-known artists and encourage people to share music purchased on the site to increase the artist's popularity.

Computer Games

Computer games sometimes use DRM technology that enforces authentication with an online server to limit the number of operating systems on which the game can be installed. Most games subject to this restriction only allow 3 to 5 copies to be installed, and some games will restore this number after being uninstalled. Not only does this limit users with more than 3 to 5 computers at home, but it also has other problems. If the user accidentally performs an operation that DRM relies on, such as an operating system upgrade or a computer hard drive format, reinstalling the game will cause authentication. The server thinks this is a new installation, thereby reducing the number of times the user can install the game, making it impossible to install even on the same computer.

The publication of " Mass Effect " in mid-2008 marked the beginning of the trend of using SecuROM to implement DRM and requiring authentication through online servers. The use of DRM for " Spore " in 2008 had the opposite effect, eventually causing a large number of users to turn to piracy. The strong resistance to the three activation certifications made " Spore " the most pirated game in the TOP 10 composed of " Spore " and "TorrentFreak" .

From the second half of 2008 to the first half of 2009, most mainstream games continued to rely on DRM based on online certification, including Electronic Arts (EA ) and Ubisoft . In early May 2010, the Uplay service was hit by a massive denial of service attack for a period as about 5% of players' games were locked . The company then made free downloads available to affected users, but then stopped.

e-book

E-books viewed on computers or e-book readers are a typical application that uses DRM to restrict copying, printing and sharing. E-books are generally limited to a certain number of readers, and some e-publishers prohibit copying or printing. Some commentators believe that DRM is one of the things that makes publishing e-books difficult.

There are four existing mainstream e-book formats: Mobipocket , Topaz, ePub , and PDF . Amazon's Kindle uses Mobipocket and Topaz and also supports e-books and documents in native PDF format. Most other e-book readers use ePub format, but it is different from DRM.

The two reading software are Adobe Reader and Microsoft Reader. Every software uses slightly different DRM. The encryption technology used by the original Adobe Acrobat e-book reader was version 5.05. In the later version 6.0, the combination of PDF reading technology and e-book reading makes it possible to read DRM-protected and free files at the same time. After opening the file, the user can read the permissions description. However, in higher-restricted e-books, users still cannot print the book or copy or paste chapters. The level of restriction is determined by publishers and intermediaries.

In one instance of DRM, a rift has been created between publishers and users. Amazon.com deleted purchased copies of George Orwell 's " 1984 " and " Animal Farm " from users' computers after paying them some compensation. This behavior has been widely referred to as Orwellianism, even referring to the dictator in 1984 .

Digital Rights Management and Documentation

Enterprise Digital Rights Management (; E-DRM or ERM for short) refers to the use of DRM technology to control the use of documents within a company rather than playable media for consumer use. This technology usually requires a policy server (Policy Server) to perform user authentication for specific documents. EDRM providers include Microsoft, Adobe , EMC /Authentica, and many small private companies.

DRM was once used by organizations like the British Library 's secure electronic delivery service, which runs large volumes of rare documents read around the world. For legal reasons, these articles were previously only accessible to authorized individuals at the Library Documentation Center in Spa, Boston, UK.

watermark

Digital watermark is a digital message hidden in video or audio data, which can be used to record copyright holders, publishers, distribution channels, buyers and other information.

Watermarks are not a complete DRM mechanism by themselves. Compared with direct technical restrictions, watermarking can preserve evidence for judicial proceedings and help copyright holders to defend their rights. Some programs can interfere with watermarks, and chromatographic analysis of signal modulators may identify and separate watermarks from the original audio. When there are two copies from different sources, the watermark can usually be detected with a home-made algorithm.

metadata

Sometimes, the metadata in the file contains information about the consumer, such as name, account information, email address, etc. This information is not embedded separately into the video or audio like a watermark, but is stored separately in the file. For example, music and video in Apple's iTunes contain metadata, which is stored in the file as MPEG standard metadata.

YouTube

In order to protect the rights and interests of creators, and to prevent digital copyright infringement due to re-uploading in the music and movie industries, YouTube has implemented the following standards to prevent abuse. At present, YouTube has the following copyright management tools in addition to filling out complaint forms:
Copyright Match Tool
Content ID
Content Verification Program
Although these tools help protect copyright, they may abuse copyright management and appeal functions. Therefore, YouTube will regulate If the user's behavior is found to be inappropriate such as abuse, the right to use, suspension or legal liability will be terminated.

law

According to the 1996 WIPO Copyright Treaty, signatory countries of the treaty are required to legislate against bypassing DRM, and most WIPO member states have implemented such regulations.

The United States implemented the Digital Millennium Copyright Act (DMCA), while Europe passed the European Copyright Directive in 2001, requiring EU countries to provide legal protection for technological protection measures. In 2006, the French lower house added similar regulations to the controversial Copyright Act in the Information Age (DADVSI), whose requirements for DRM interoperability have also sparked controversy in the United States. In the same year, the French High Court ruled that under the French copyright law, the act of privately making backups by individuals should not be hindered.

USA

Article: Digital Millennium Copyright Act

On May 14, 1998, the United States passed the copyright amendment "Digital Millennium Copyright Act" (DMCA), which made bypassing DRM a crime.

The Act's protected harbor provisions specifically allow reverse engineering of existing systems, but only to the extent necessary to achieve software interoperability. When encountering open source software like DeCSS , a problem hidden in the bill is difficult to solve, causing the judgment of the case to a large extent depends on the subjective intention of the parties. When the party's subjective intention is to improve the interoperability between open source systems and proprietary systems, the act of cracking the encryption system is protected by law, and vice versa.

The DMCA fails to protect the DRM system in many cases. However, those who want to protect DRM have tried to use legislation to restrict the development and distribution of software such as DeCSS.

European Union

On April 25, 2007, the European Parliament endorsed the First Directive from the European Union aimed at harmonizing criminal law within Member States. It adopted the initial review report to unify national policy in the fight against abuse of authority. If the European Parliament and the Commission agree to the legislation, member states will have to consider commercially infringing copyright practices. The report offers a wide range of recommendations: ranging from fines to prison terms, depending on the severity of the crime. EU member states backed the Commission's decision after amending some of its content. They excluded some directives from patent rights and decided to penalize copyright infringement for commercial purposes only.

international issues

There are a number of active dialogue mechanisms in Europe that try to build consensus on such issues:

• January 2001, World Wide Web Consortium (W3C) DRM Symposium.
• 2003 Early Call for Proposals for CEN/ISSS DRM Report.
• The DRM Working Group of the Information Security and Media Regular Board, the same DRM work for the high-level organization.
• Consultation of the European Commission, The Defense Internal Market, Communication of the European Commission on "Management of Copyright and Related Rights" (closing).
• In Europe, the INDICARE project is an ongoing study of user acceptance of DRM solutions. It is a developed, neutral platform for the exchange of opinions, mostly articles and practices from writers in the scientific community.
• AXMEDIS Engineering within European Commission FP6. Its main purpose is to automate the process of content production, copy protection and distribution, reduce related costs, coordinate and support the application of DRM in the B2B and B2C fields.

debate

Opponents of DRM

A simple parody of the Home Taping Is Killing Music icon.

Members of "Flaws by Design" ( ) are fighting against DRM.

Many organizations, individuals, and computer scientists are against DRM. Two prominent opponents of DRM, one of them John Walker, said in his book "Digital Publishing Licensing": "How powerful will it take Big Brother and the media to put this Internet genie back in the bottle? ? (How big brother and big media can put the Internet genie back in the bottle)" Another is Richard Stallman, who once argued in his book "Reading Rights": "DRM is a typical malicious function—— This feature was designed to harm its users, so we will not tolerate it." Other prominent opponents include Cambridge University professor Ross Anderson, who founded an anti-DRM organization in the UK, and author Corley, who gave a speech on the Microsoft campus criticizing DRM. Doctorow.

The Freedom Information Framework believes that DRM is a trade barrier to free trade , and the Electronic Frontier Foundation and FreeCulture.org also oppose DRM.

Chapter 3 of the GNU General Public License declares that the anti-cracking provisions of copyright law do not apply to GPL software, so users can modify the restrictions in GPL software at will without worrying about violating copyright laws like DMCA. In May 2006, the Free Software Foundation launched an anti-DRM campaign called " Flaws by Design " ().

Creative Commons provides licenses to support creative work without the use of DRM.

Bill Gates gave a speech on DRM at CES in 2006. According to him, DRM should not cause confusion to legitimate users because of its current position, distinguishing between legal and illegal.

Many opponents of DRM feel that calling DRM "digital rights management" is a misnomer.

In 2007, the Norwegian consumer rights organization "Forbrukerrådet" launched a complaint against Apple. Apple is accused of illegally restricting users' access to audio and video, in violation of Norwegian consumer protection law, because of the DRM used by iPods and iTunes. The Swedish and Danish consumer ombudsmen supported the complaint. Similarly, the US Federal Trade Commission conducted hearings in March 2009 to investigate merchant notifications of DRM restrictions.

The use of DRM is also a perplexity for future historians. With the step-by-step development of technology, the interpretation of data can only be carried out through specific machines, keys or periods, which may make future data interpretation work impossible.

Opponents believe that DRM affects the normal use of products by legal users and violates private property rights . DRM systems control how users use devices and software, impose restrictions against users' will, and violate users' right to dispose of their devices. Doctorow likened it to "giving copyright holders the power to write copyright laws".

DRM-free (DRM-free)

The DRM-free logo proposed by the Free Software Foundation

In response to consumer opposition to DRM, many publishers and artists are promoting "DRM-free" as a selling point. Companies that do this include:

• Apple 's iTunes music store. Although released with DRM in 2003, DRM-free music has been available since April 2007, and all music sold after January 2009 is DRM-free. The music still carries a digital watermark used to identify the buyer . Other items on iTunes, such as movies, TV shows, ringtones and audiobooks, continue to use DRM.
• ComiXology, an electronic comic distributor owned by Amazon. In 2014, ComiXology offered publishers the option to distribute without using DRM. Publishers who have chosen not to use DRM include Image Comics , Dynamite Entertainment, Thrillbent, Top Shelf Productions, Zenescope Entertainment, and others.
• GOG.com , a computer game distributor founded in 2008. Unlike most distributors, GOG.com requires games to be DRM-free for its store.
• Tor Books, a major science fiction publishing house. DRM-free eBooks have been available since July 2012. Small publishers such as Baen Books and O'Reilly Media have previously sold DRM-free e-books.

mission Impossible

Bruce Schneier has stated that defending against digital copying is useless and claims that it is an impossible task. He said: "The entertainment industry is trying to use technology to fight against the laws of nature. They want to protect the existing industry by making it more difficult to copy, but they are doomed to fail." He also once compared the act of preventing the copying of digital files to " Keep the water from getting wet." The founder of StarForce took the same view, claiming that "the result of preventing copying will not make the game uncrackable - it is impossible." Gabe Newell, chairman of Valve Software Corporation, also stated: "Most of the DRM is dumb" because they only reduce the value of the game in the eyes of the player. Newell proposes to combat this kind of piracy by "creating value for the user with the value of the service".

Both the Association for Computing Machinery and the Institute of Electrical and Electronics Engineers have also opposed DRM, and even a technology like AACS "almost failed."

limitation

Ways to Bypass DRM

For audio and video, there are many ways to bypass digital copyright controls.

An easy way to bypass DRM on audio files is to use CD burning software to copy the CD audio to the hard drive and convert it to a DRM-free file. This is only possible if the software that plays these DRM-restricted audio allows CD burning. Some software products simplify and automate the copying and burning process by allowing the user to copy music to a CD or virtual drive, then automatically burn and encode the music, and loop until all selected music is converted, rather than forcing the user to To do one operation on the entire CD (72-80 minutes of music).

A lot of software has been developed that intercepts the stream of data decoded from a DRM-restricted file and constructs a DRM-free file. Such software requires a decryption key. Software like this that does things for DVD, HD DVD, and Blu-ray Discs contains the universal decryption key itself. However, the software that does the same for TiVo ToGo recordings, iTunes audio, and PlaysForSure songs relies on the user's own keys—that is, they can only process content that the user has legally acquired under their account.

Another method is to take advantage of the simulation loopholes , use software to capture the information in the graphics card or sound card, or directly use hardware devices to record at the output port.

DRM on general computer platforms

Many of the DRM systems currently in use are designed for general-purpose computer hardware, such as the PC, apparently because it is well suited to prevent damage from unauthorized copying. Large commerce protects infringers from consumer devices, so losses caused by such infringers are not covered by such provisions.

Such schemes, especially those based on software, cannot be completely secure since the software must contain all the information needed to decrypt the content, such as decryption keys. An attacker can extract this information and directly decrypt and copy the content that bypasses the restrictions.

DRM on custom hardware

The encrypted media used by many DRM schemes requires custom hardware to view and view the content. This is to ensure that only licensed users (those who use the hardware) get access to the content. Additionally it tries to protect secret encryption keys from system users.

While this set of principles works, it is indeed difficult to build hardware that prevents secret keys from being discovered by a determined adversary. Many such systems have failed in this area. Once the secret key is known, no checks are made, and building new versions of the hardware is usually quite simple. In addition, user authentication rules are often attacked, and pirate decryption is the most frequently attacked.

A common real-world example can be found in financial direct broadcast satellite TV stations such as DirecTV and Astro in Malaysia. The company uses tamper-resistant smart cards to store decryption keys so they can be hidden from users and satellite receivers. However, the system has broken and DirecTV has been forced to no longer regularly update and replace its smart cards.

watermark

This is typically the case and the watermark can be removed, although video or audio degradation will occur.

replay attack

Entry: Replay attack

Analogous to the replay attack of cryptography, the redistribution of digital copies does not actually need to break the DRM encryption, as long as the exact same copy is copied. For example, an encrypted disc can be transmitted over the network, re-burned and then viewed on a legal player.

easy to be eliminated

When technical standards or formats change, DRM-restricted content may not be converted to new media and become invalid. For example, the new player Zune launched by Microsoft does not support the DRM mechanism previously adopted by Microsoft, and cannot play music using PlaysForSure. In addition, the DRM that requires online authentication may also encounter the problem of server unavailability. For example, when the American Major League Baseball (mlb.com) changed the verification license service in 2007, all paid videos purchased by users for the 2006 season could not be played. After the company's business reorganization, the content of the abandoned business may also become outdated and no longer available. Examples include Amazon e-books, MSN music, Yahoo music store, etc.

Implications for Ethics and Regulations

“In order to attract customers, music services use budget-conscious marketing to mask the restrictions they impose on customers,” the EFF noted.

Laws on DRM are rarely strictly enforced. According to Australia's official music ranking survey, millions of people have participated in various infringements.

The loss outweighs the gain

Jeff Raikes, former director of the Microsoft Division, once said: "If anyone wants to crack software, we hope that we are the one who is cracked, not someone else." Kathleen Conner and Richard Rummelt also gave a similar in a paper argument. In a follow-up study, Gal Oestreicher-Singer and Arun Sundararajan pointed out that liberalizing DRM restrictions can benefit digital rights owners, because the added value of more legitimate users outweighs the losses caused by piracy.

other business models

Several business models are considered to replace the current business model and reduce the industry's need to use DRM.

easy and cheap

Improving the usability and cost-effectiveness of genuine products is the preferred method of preventing piracy. It is not convenient to use download sites to obtain pirated copies. Searching and downloading requires time and effort, and you also have to bear the risk of virus infection. If there are legitimate, user-friendly stores offering genuine copies at reasonable prices, users will trade illegal downloads for convenience.

Crowdfunding and pre-orders

In February 2012, Double Fine Productions raised funds for the game " Broken Time " in the form of crowdfunding on Kickstarter , promising that crowdfunders can obtain DRM-free games. Within 45 days, the crowdfunding project reached the target amount of $400,000, and finally exceeded the target amount by more than $2 million. This crowdfunding used the non-use of DRM as a selling point, and gained the support of consumers and the media, thus balancing the losses caused by piracy. In this kind of pre-order crowdfunding, manufacturers no longer need to worry about sales not being able to cover their expenses, reducing the incentive to use DRM. Following the success of Shattered Times, many games have adopted the crowdfunding business model, most of which do not use DRM.

Digital Products as Publicity

Many singers boost their popularity by releasing their music online. The songs are all available for free download online, and it is hoped that listeners who are interested will buy new records or attend concerts. Current industry practice is to release one or two songs from an album for free online, with the rest only available on disc. In 2007, the Radiohead band released the album "Rainbows" online, and fans can download songs freely online.

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