A closed platform', walled garden or  is a software system where the carrier or service provider has control over applications, content, and media and restricts convenient access to non-approved applications or content. This is in contrast to an open platform, where consumers have unrestricted access to applications and content.
For example in telecommunications, the services and applications accessible on any cell phone on any given wireless network were tightly controlled by the mobile operators. The mobile operators limited the applications and developers that were available on users' home portals and home pages. This can happen when users have no pre-paid money left on their account as a result service provider has restricted user access. This has long been a central issue constraining the telecommunications sector, as developers face huge hurdles in making their applications available to end-users.
In a more extreme example, with the pre-regulated 1970s American telephone system, "Ma Bell" virtually owned all the hardware (including all phones) and all the signals, and virtually even the words (information) on their wires. The words did not become yours until they left the Ma Bell earpiece (or other Ma Bell output device) and entered your ear. It was illegal for the user to even monitor or record the signals near "his own" phone with a non-Bell magnetic pic-up device. In that case, this was an openly government sanctioned and regulated monopoly.
More generally, a "walled garden" refers to a closed or exclusive set of information services provided for users. Similar to a real walled garden, a user in a walled garden is unable to escape this area unless it is through the designated entry/exit points or the walls are removed.
Some examples of walled gardens:
- Amazon. The Amazon Kindle line of eReaders uses a walled garden. As an October 2011 Business Insider article, titled "How Amazon Makes Money From The Kindle" observes: "Amazon's Kindle is no longer just a product: It's a whole ecosystem." Moreover, "The Kindle ecosystem is also Amazon's fastest-growing product and could account for more than 10% of the company's revenue next year."
- Apple iOS and other devices restricted to running pre-approved applications from a digital distribution service.
- Barnes & Noble. In late December 2011, B&N began pushing the automatic, over-the-air firmware update 1.4.1 to Nook Tablets that removed users' ability to gain root access to the device and the ability to sideload applications from sources other than the official Barnes and Noble NOOK Store (without modding).
- Verizon Wireless's CDMA network and policies effectively prohibiting activation of non-Verizon sanctioned devices on their network. Verizon Wireless is frequently noted (and often criticized) for this practice.
- Video game consoles have a long history of walled gardens, with developers needing to purchase licenses to develop for the platform, and in some cases needing editorial approval from the console manufacturer prior to publishing games.
- Business ecosystem
- Damaged good
- Defective by Design
- Gated community
- Hardware restriction
- Software protection dongle
- Daniel Memetic. "Escaping the Walled Gardens in the Clouds". Tech-FAQ.com. Retrieved 7 October 2012.
- Nicholas Smith (2009). "Interview With Rosabeth Moss Kanter, author of SuperCorp (2009): No Matter How Big You Are, Diversify or Die". Ericsson.com Company Docs. Retrieved 7 October 2012.
- "Definition of: walled garden". PCmag.com. Retrieved 13 June 2012.
- Mathew Ingram (Feb 29, 2012). "How the e-book landscape is becoming a walled garden". Gigaom. Retrieved 7 October 2012.
- Jay Akasie (Sep 07, 2012). "With New Kindle, Bezos Proves Ecosystems Matter More Than Hardware". Retrieved 7 October 2012.
- Pascal-Emmanuel Gobry (October 18, 2011). "How Amazon Makes Money From The Kindle; Amazon's Kindle is no longer just a product: It's a whole ecosystem". Business Insider. Retrieved 29 November 2013.
- Charles Arthur, technology editor (17 April 2012). "Battle for the Internet (Part III of series): Walled gardens look rosy for Facebook, Apple – and would-be censors". The Guardian.
- Ben Bajarin (1 July 2011). "Why Competiting With Apple is So Difficult". TIME.
- Smith, Peter (December 21, 2011). "Kindle Fire and Nook Tablet both get "upgraded" with reduced functionality". ITWorld.com. Retrieved 10 January 2012.
- Verry, Tim (December 21, 2011). "Kindle Fire and Nook Tablet Receive Root Access Killing Software Updates". PCPerspective.com. Retrieved 10 January 2012.
- "Walled gardens are great when a medium is brand new. Without history and without...". Retrieved 29 November 2013.
- Martin Adolph of ITU’s Telecommunication Standardization Bureau (TSB) (2011). "The world of video games: Trends in video games and gaming". ITU News (10).
- Robert A. Burgelman & Carrie C. Oliver (August 1, 1997). "Electronic Arts in 1995". Stanford Graduate School of Business. pp. 16 pages. Retrieved 29 November 2013. "isbn=Prod. #: SM24-PDF-ENG"