A closed platform, walled garden or closed ecosystem 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 generally have unrestricted access to applications and content.
For example, in telecommunications, the services and applications accessible on a cell phone on any given wireless were formerly tightly controlled by the mobile operators. The operators limited the applications and developers that were available on users' home portals and home pages. Thus, a service provider might restrict user access to users whose account exhausted the pre-paid money on their account. 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, Bell owned all the hardware (including all phones) and had indirect control over the information sent through their infrastructure. A landmark case was Hush-A-Phone v. United States, wherein Bell unsuccessfully sued a company producing plastic telephone attachments. In the case of Bell, it was an openly government sanctioned and regulated monopoly by the Communications Act of 1934.
More generally, a walled garden can refer 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.
An 2008 paper from the Harvard Business School differentiated a platform's openness/closedness by four aspects and gave example platforms.
Some examples of walled gardens:
In the 1990s AOL developed what was later called its "walled garden" model of service. The idea was to preferentially offer sponsored content to users when possible. During this period, CBS paid to provide sports content, ABC paid to provide news, and 1-800-Flowers paid to be the default florist for anyone seeking one. This strategy became AOL's first good method for selling advertisements. In its time, this method was highly profitable to AOL.
Amazon's Kindle line of eReaders. 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, as Business Insider noted in "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 mobile devices, which are restricted to running pre-approved applications from a digital distribution service.
Barnes & Noble's NOOK devices. 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). NOOK HD and HD+ devices were similarly "closed", until May 2013, when BN opened its ecosystem somewhat by permitting users to install the Google Play Store and the various Android apps offered there, including those of rivals, such as Audible.com, comiXology, Kindle, Kobo, and Google itself.
Verizon Wireless' 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.
