Tivoization Explained

Tivoization is the practice of designing hardware that incorporates software under the terms of a copyleft software license like the GNU General Public License (GNU GPL), but uses hardware restrictions or digital rights management (DRM) to prevent users from running modified versions of the software on that hardware. Richard Stallman of the Free Software Foundation (FSF) coined the term in reference to TiVo's use of GNU GPL licensed software on the TiVo brand digital video recorders (DVR), which actively block modified software by design.[1] [2] Stallman believes this practice denies users some of the freedom that the GNU GPL was designed to protect.[3] The FSF refers to tivoized hardware as "proprietary tyrants".[4]

The Free Software Foundation explicitly forbade tivoization in version 3 of the GNU General Public License. However, although version 3 has been adopted by many software projects, the authors of the Linux kernel have notably declined to move from version 2 to version 3.

Background

TiVo's software incorporates the Linux kernel and GNU software, both of which are licensed under version 2 of the GNU General Public License (GPLv2). GPLv2 requires distributors to make the corresponding source code available to each person who receives the software. One goal of this requirement is to allow users of GPL-covered software to modify the software to better suit their purposes.[5]

Richard Stallman of the Free Software Foundation asserts that TiVo circumvented the GPL's goal by making their products run programs only if the program's digital signature matches those authorized by the manufacturer of the TiVo.[6] While TiVo has complied with the GPL v2 requirement to release the source code for others to modify, any modified software will not run on TiVo's hardware.

Bradley Kuhn of the Software Freedom Conservancy disputes Stallman's narrative. Kuhn asserts that TiVo did not strictly forbid software replacement, but TiVo's proprietary software was intentionally designed to not function if any open-source components were replaced, which consequently required the user to find fully open-source alternatives to the proprietary software. In Kuhn's view, TiVo did not tivoize, the GPLv2 was already sufficient to prevent tivoization, and the intent of the GPLv3 was to add an additional, unnecessary requirement that proprietary software continue to function.[7]

GNU GPLv3

In 2006, the Free Software Foundation (FSF) decided to combat TiVo's technical system of blocking users from running modified software. The FSF subsequently developed a third version of the GNU General Public License (GPLv3) which was designed to include language which prohibited this activity.[8] According to Eben Moglen, "the license should prohibit technical means of evasion of its rules, with the same clarity that it prohibits legal evasion of its rules."[9]

The second draft of the GPLv3 attempted to clarify the rules regarding tivoization.[10] However, some Linux kernel developers were still concerned that this draft might still prohibit beneficial uses of digital signatures.[11] Stallman and the Free Software Foundation attempted to respond to some of these concerns by stating that the GPLv3 allows private digital signatures for security purposes while still preventing tivoization.

In the third and fourth discussion drafts of the GPLv3, released March 28, 2007 and May 31, 2007, respectively, the anti-tivoization clause was limited so as not to apply when the software is distributed to a business.[12] Thus, medical devices and voting machines would not be covered. The final, official GPLv3 was published on June 29, 2007, with no major changes in respect to tivoization relative to the fourth draft.

Linus Torvalds said he was "pretty pleased" with the new draft's stance on DRM.[13] However, he still does not support relicensing the Linux kernel under GPLv3, stating that:[14]

The GPLv3's new license provisions were acknowledged by TiVo in its April 2007 SEC filing: "If the currently proposed version of GPLv3 is widely adopted, we may be unable to incorporate future enhancements to the GNU/Linux operating system into our software, which could adversely affect our business."[15]

Outcome

The Linux kernel, which is included in the operating system of TiVo-branded hardware, is still distributed under the terms of the GPLv2. The kernel has not been changed to use GPLv3[16] because the kernel maintainers have generally perceived the GPLv3 to be overly restrictive,[17] [18] [19] although some kernel developers, such as Alan Cox,[20] have expressed divergent opinions. In any case, offering the Linux kernel under a different license would likely be infeasible because of its very large number of copyright holders. Unlike most GPL software, the kernel is licensed only under GPLv2 without the wording "or, at your option, any later version", therefore the explicit agreement of all copyright holders would be required to license the kernel as a whole under a new version.[21]

Some other projects widely used in tivoized embedded systems, such as BusyBox, have also declined to move to GPLv3.[22]

See also

Further reading

Notes and References

  1. Web site: Frequently Asked Questions about the GNU Licenses . March 17, 2015 . live . https://web.archive.org/web/20161229211715/https://www.gnu.org/licenses/gpl-faq.html . December 29, 2016. GNU.org Frequently Asked Questions about the GNU Licenses
  2. Web site: A Quick Guide to GPLv3 . March 17, 2015 . live . https://web.archive.org/web/20161229211618/https://www.gnu.org/licenses/quick-guide-gplv3.html . December 29, 2016. A Quick Guide to GPLv3
  3. Web site: [Info-gplv3] GPLv3 Update #2 ]. https://web.archive.org/web/20061026084218/http://gplv3.fsf.org/pipermail/info-gplv3/2006-February/000001.html . dead . October 26, 2006 . fsf.org . October 2, 2015.
  4. Web site: Proprietary Tyrants . Free Software Foundation . January 28, 2023. https://web.archive.org/web/20150924024955/http://www.gnu.org/proprietary/proprietary-tyrants.html . September 24, 2015 . live.
  5. Web site: The Free Software Definition . ...The freedom to study how the program works, and adapt it to your needs... . January 28, 2023 . https://web.archive.org/web/20230127163705/https://www.gnu.org/philosophy/free-sw.html . January 27, 2023 . live.
  6. Web site: Using large disks with TiVo . gratisoft.us . October 2, 2015 . https://web.archive.org/web/20120206023943/http://www.gratisoft.us/tivo/bigdisk.html . February 6, 2012 . dead.
  7. Web site: Kuhn . Bradley . Bradley M. Kuhn . "Tivoization" and Your Right to Install Under Copyleft . Conservancy Blog . 6 April 2023 . 23 July 2021.
  8. Web site: Richard Stallman explains the new GPL provisions to block "tivoisation" . January 28, 2023 . https://web.archive.org/web/20221006035111/https://fsfe.org/activities/gplv3/brussels-rms-transcript#tivoisation . October 6, 2022 . live.
  9. Web site: Eben Moglen, speaking about GPLv3 in Barcelona . January 28, 2023 . https://web.archive.org/web/20230112031229/https://fsfe.org/activities/gplv3/barcelona-moglen-transcript.en.html#drm . January 12, 2023 . live.
  10. Web site: Opinion on Digital Restrictions Management . fsf.org . October 2, 2015 . https://web.archive.org/web/20060819170543/http://gplv3.fsf.org/drm-dd2.html . August 19, 2006 . live.
  11. Web site: GPLv3 Position Statement . September 22, 2006 . James E.J. . Bottomley . Mauro Carvalho . Chehab . Thomas . Gleixner . Christoph . Hellwig . Dave . Jones . Greg . Kroah-Hartman . Tony . Luck . Andrew . Morton . Trond . Myklebust . David . Woodhouse . google.com . October 2, 2015 . https://web.archive.org/web/20211202200652/https://groups.google.com/g/linux.kernel/c/IdRykVVBrEg/m/9XX1lwMDrTYJ . December 2, 2021 . live.
  12. Web site: brett . GPLv3 FAQ, with explanation of Section 6's limits | . 2007-06-26 . January 28, 2023 . https://web.archive.org/web/20070606082643/http://gplv3.fsf.org/dd3-faq . June 6, 2007 . live.
  13. Web site: Torvalds 'pretty pleased' about new GPL 3 draft . CNet news.com . https://archive.today/20120713115859/http://news.cnet.com/8301-10784_3-6171300-7.html . July 13, 2012.
  14. Web site: Re: Dual-Licensing Linux Kernel with GPL V2 and GPL V3 . Linus . Torvalds . Linux Kernel Mailing List . June 13, 2007 . January 28, 2023 . https://web.archive.org/web/20070617234347/http://lkml.org/lkml/2007/6/13/289 . June 17, 2007 . live.
  15. Web site: InformationWeek: TiVo Warns Investors New Open Source License Could Hurt Business. June 1, 2007 . https://web.archive.org/web/20220727084236/https://www.informationweek.com/software/tivo-warns-investors-new-open-source-license-could-hurt-business . July 27, 2022 . live.
  16. Web site: COPYING . Also note that the only valid version of the GPL as far as the kernel is concerned is _this_ particular version of the license (ie v2, not v2.2 or v3.x or whatever), unless explicitly otherwise stated. . August 13, 2013 . kernel.org . Linus . Torvalds . blob ca442d313d86dc67e0a2e5d584b465bd382cbf5c . https://web.archive.org/web/20230128083313/https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/COPYING?id=b3358a116c25267446a45e4164cb2b8e98276da0 . January 28, 2023 . live .
  17. Web site: Kernel developers' position on GPLv3 – The Dangers and Problems with GPLv3 . James E.J. . Bottomley . Mauro Carvalho . Chehab . Thomas . Gleixner . Christoph . Hellwig . Dave . Jones . Greg . Kroah-Hartman . Tony . Luck . Andrew . Morton . Trond . Myklebust . David . Woodhouse . September 15, 2006 . . March 11, 2015 . "The current version (Discussion Draft 2) of GPLv3 on first reading fails the necessity test of section 1 on the grounds that there's no substantial and identified problem with GPLv2 that it is trying to solve. However, a deeper reading reveals several other problems with the current FSF draft: 5.1 DRM Clauses [...] 5.2 Additional Restrictions Clause [...] 5.3 Patents Provisions [...]since the FSF is proposing to shift all of its projects to GPLv3 and apply pressure to every other GPL licensed project to move, we foresee the release of GPLv3 portends the Balkanisation of the entire Open Source Universe upon which we rely." . https://web.archive.org/web/20060925172439/http://lwn.net/Articles/200422/ . September 25, 2006 . live.
  18. Linus Torvalds says GPL v3 violates everything that GPLv2 stood for . September 4, 2014 . March 11, 2015 . https://web.archive.org/web/20161119072821/https://www.youtube.com/watch?v=PaKIZ7gJlRU . November 19, 2016 . live . Debconf 2014 . Portland.
  19. Web site: fa.linux.kernel: Linus Torvalds: Flame Linus to a crisp! . April 24, 2003 . google.com . December 27, 2020 . https://web.archive.org/web/20201227002332/https://groups.google.com/g/fa.linux.kernel/c/L5NRD_ONkIk . December 27, 2020 . live.
  20. Web site: UK Linux guru backs GPL 3 . https://web.archive.org/web/20090428180852/http://news.zdnet.co.uk/software/0,1000000121,39249913,00.htm . ZDNet . January 31, 2006 . October 2, 2015 . April 28, 2009 . dead.
  21. Web site: (About GPLv3) Can the Linux Kernel Relicense? — Ciarán's free software notes . Mark P. Lindhout . October 16, 2006 . fsfe.org . October 2, 2015 . https://web.archive.org/web/20090223105632/http://blogs.fsfe.org/ciaran/?p=58 . Feb 23, 2009 . live.
  22. Web site: Busy busy busybox . LWN . January 28, 2023 . https://web.archive.org/web/20061105234312/http://lwn.net/Articles/202106/ . November 5, 2006 . live.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Tivoization".

Except where otherwise indicated, Everything.Explained.Today is © Copyright 2009-2024, A B Cryer, All Rights Reserved. Cookie policy.