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{{Short description|Wi-Fi standard for peer-to-peer wireless connections}}{{More citations needed|date=March 2020}}Wi-Fi Direct (formerly Wi-Fi Peer-to-Peer) is a Wi-Fi standard for peer-to-peer wireless connectionsWEB,weblink Wi-Fi Direct, Wi-Fi Alliance, Wi-Fi.org, 2013-07-30, that allows two devices to establish a direct Wi-Fi connection without an intermediary wireless access point, router, or Internet connection. Wi-Fi Direct is single-hop communication, rather than multi-hop communication like wireless ad hoc networks.Wi-Fi becomes a way of communicating wirelessly, much like Bluetooth. It is useful for everything from internet browsing to file transfer,WEB,weblink Can a network based on devices certified under the Wi-Fi Direct program cross connect to an infrastructure network for Internet connectivity?, Wi-Fi Alliance, Wi-Fi.org, 2013-07-30, dead,weblink" title="web.archive.org/web/20130403025145weblink">weblink April 3, 2013, WEB, Griffith, Eric,weblink New 'Wi-Fi Direct' Spec Revamps Device Networks | News & Opinion, PCMag.com, 2009-10-14, 2013-07-30, and to communicate with one or more devices simultaneously at typical Wi-Fi speeds.WEB,weblink How fast is Wi-Fi Direct?, Wi-Fi Alliance, Wi-fi.org, 2013-07-30, One advantage of Wi-Fi Direct is the ability to connect devices even if they are from different manufacturers. Only one of the Wi-Fi devices needs to be compliant with Wi-Fi Direct to establish a peer-to-peer connection that transfers data directly between them with greatly reduced setup.WEB,weblink Simple Questions: What Is WiFi Direct? How Does It Work?, 19 May 2015, DigitalCitizen.life, 12 April 2018, Wi-Fi Direct negotiates the link with a Wi-Fi Protected Setup system that assigns each device a limited wireless access point. The "pairing" of Wi-Fi Direct devices can be set up to require the proximity of a near field communication, a Bluetooth signal, or a button press on one or all the devices.

Background

Basic Wi-Fi

Conventional Wi-Fi networks are typically based on the presence of controller devices known as wireless access points. These devices normally combine three primary functions:

• Physical support for wireless and wired networking
• Bridging between devices on the network
• Service provisioning to add and remove devices from the network.{{cn|date=February 2022}}

A typical Wi-Fi home network includes laptops, tablets and phones, devices like modern printers, music devices, and televisions. Most Wi-Fi networks are set up in infrastructure mode, where the access point acts as a central hub to which Wi-Fi capable devices are connected. All communication between devices goes through the access point. In contrast, Wi-Fi Direct devices are able to communicate with each other without requiring a dedicated wireless access point. The Wi-Fi Direct devices negotiate when they first connect to determine which device shall act as an access point.{{cn|date=February 2022}}

Automated setup

With the increase in the number and type of devices attaching to Wi-Fi systems, the basic model of a simple router with smart computers became increasingly strained. At the same time, the increasing sophistication of the hot spots presented setup problems for the users. To address these problems, there have been numerous attempts to simplify certain aspects of the setup task.A common example is the Wi-Fi Protected Setup system included in most access points manufactured since 2007 when the standard was introduced.WEB,weblink Wi-Fi Protected Setup, Wi-Fi Alliance Knowledge base, Wi-Fi Protected Setup allows access points to be set up simply by entering a PIN or other identification into a connection screen, or in some cases, simply by pressing a button. The Protected Setup system uses this information to send data to a computer, handing it the information needed to complete the network setup and connect to the Internet. From the user's point of view, a single click replaces the multi-step, jargon-filled setup experience formerly required.While the Protected Setup model works as intended, it was intended only to simplify the connection between the access point and the devices that would make use of its services, primarily accessing the Internet. It provides little help within a network - finding and setting up printer access from a computer for instance. To address those roles, a number of different protocols have developed, including Universal Plug and Play (UPnP), Devices Profile for Web Services (DPWS), and zero-configuration networking (ZeroConf). These protocols allow devices to seek out other devices within the network, query their capabilities, and provide some level of automatic setup.

Wi-Fi Direct

Wi-Fi Direct has become a standard feature in smart phones and portable media players, and in feature phones as well.Glenn Fleishman, "Broadcom squeezes 11n, Bluetooth, FM into new, cheap chip", Ars Technica, 8 December 2008 The process of adding Wi-Fi to smaller devices has accelerated, and it is now possible to find printers, cameras, scanners, and many other common devices with Wi-Fi in addition to other connections, like USB.The widespread adoption of Wi-Fi in new classes of smaller devices made the need for ad hoc networking much more important. Even without a central Wi-Fi hub or router, it would be useful for a laptop computer to be able to wirelessly connect to a local printer. Although the ad hoc mode was created to address this sort of need, the lack of additional information for discovery makes it difficult to use in practice.Eric Griffith, "New 'Wi-Fi Direct' Spec Revamps Device Networks", PCMag.com, 14 October 2009Olga Kharif, weblink" title="web.archive.org/web/20091017025633weblink">"Wi-Fi Is About to Get a Whole Lot Easier", BusinessWeek, 14 October 2009Although systems like UPnP and Bonjour provide many of the needed capabilities and are included in some devices, a single widely supported standard was lacking, and support within existing devices was far from universal. A guest using their smart phone would likely be able to find a hotspot and connect to the Internet with ease, perhaps using Protected Setup to do so. But, the same device would find that streaming music to a computer or printing a file might be difficult, or simply not supported between differing brands of hardware.Wi-Fi Direct can provide a wireless connection to peripherals. Wireless mice, keyboards, remote controls, headsets, speakers, displays, and many other functions can be implemented with Wi-Fi Direct. This has begun with Wi-Fi mouse products, and Wi-Fi Direct remote controls that were shipping circa November 2012.File sharing applications such as SHAREit on Android and BlackBerry 10 devices could use Wi-Fi Direct, with most Android version 4.1 (Jellybean), introduced in July 2012, and BlackBerry 10.2 supported. Android version 4.2 (Jellybean) included further refinements to Wi-Fi Direct including persistent permissions enabling two-way transfer of data between multiple devices.The Miracast standard for the wireless connection of devices to displays is based on Wi-Fi direct.{{Citation needed|date=March 2023}}

Technical description

Wi-Fi Direct essentially embeds a software access point ("Soft AP") into any device that must support Direct. The soft AP provides a version of Wi-Fi Protected Setup with its push-button or PIN-based setup.When a device enters the range of the Wi-Fi Direct host, it can connect to it, and then gather setup information using a Protected Setup-style transfer. Connection and setup is so simplified that it may replace Bluetooth in some situations.Chris Foresman, "Wi-Fi Direct protocol to ease peer-to-peer WiFi connections", Ars Technica, 14 October 2009Soft APs can be as simple or as complex as the role requires. A digital picture frame might provide only the most basic services needed to allow digital cameras to connect and upload images. A smart phone that allows data tethering might run a more complex soft AP that adds the ability to route to the Internet. The standard also includes WPA2 security and features to control access within corporate networks. Wi-Fi Direct-certified devices can connect one-to-one or one-to-many and not all connected products need to be Wi-Fi Direct-certified. One Wi-Fi Direct enabled device can connect to legacy Wi-Fi certified devices.The Wi-Fi Direct certification program is developed and administered by the Wi-Fi Alliance, the industry group that owns the "Wi-Fi" trademark. The specification is available for purchase from the Wi-Fi Alliance.WEB,weblink Wi-Fi Alliance Published Specifications, Wi-Fi Alliance, 2013-07-30,

Commercialization

Laptops

Intel included Wi-Fi Direct on the Centrino 2 platform, in its My WiFi technology by 2008.WEB, Welcome to the Freedom of Portable Wi-Fi; Intel My WiFi Technology: Synch, Share, Show & Print on the Go, December 3, 2008, Intel, Promotional brochure,weblink dead,weblink" title="web.archive.org/web/20090205013444weblink">weblink February 5, 2009, September 27, 2013, Wi-Fi Direct devices can connect to a notebook computer that plays the role of a software Access Point (AP). The notebook computer can then provide Internet access to the Wi-Fi Direct-enabled devices without a Wi-Fi AP. Marvell Technology Group,WEB,weblink Marvell supports new 'Wi-Fi Direct' standard across entire line of 802.11 devices, Marvell, Press release, October 14, 2009, September 27, 2013, Atheros, Broadcom, Intel, Ralink, and Realtek announced their first products in October 2010.WEB, W. David Gardner,weblink Wi-Fi Direct Products Connect without a Network, Informationweek.com, 2010-10-25, 2013-07-30, Redpine Signals's chipset was Wi-Fi Direct certified in November of the same year.WEB,weblink Redpine Signals' Lite-Fi – Ultra Low Power 802.11n – RS9110 Chipset Achieves Wi-Fi Direct™ Certification, Redpinesignals.com, 2013-07-30,

Mobile devices

File:Wi-Fi Direct Android Icon.png|thumb|An icon to indicate Wi-Fi Direct operation under Android ]]Google announced Wi-Fi Direct support in Android 4.0 in October 2011.WEB,weblink Android 4, Developer.android.com, 2013-07-30, While some Android 2.3 devices like Samsung Galaxy S II have had this feature through proprietary operating system extensions developed by OEMs, the Galaxy Nexus (released November 2011) was the first Android device to ship with Google's implementation of this feature and an API for developers. {{Citation needed|date=May 2014}}Ozmo Devices, which developed integrated circuits (chips) designed for Wi-Fi Direct, was acquired by Atmel in 2012.WEB, Atmel Wi-Fi buy aimed at Internet of Things, Peter Clarke, EE Times, December 21, 2012,weblink September 27, 2013, NEWS, RFaxis and Ozmo Devices Collaborate to Enable 5 GHz Wi-Fi Direct Surround Sound Home Theater Systems, December 18, 2012, Press release,weblink September 27, 2013, Wi-Fi Direct became available with the BlackBerry 10.2 upgrade.WEB,weblink Wi-Fi Direct - BlackBerry Developer, 2015-03-21, WEB,weblink Directions for Wi-Fi Direct Connection with Your App - BlackBerry Developer Blog, 2015-03-21, {{As of|2016|03|post=,}} no iPhone device implements Wi-Fi Direct; instead, iOS has its own proprietary feature, namely Apple's MultipeerConnectivity.WEB,weblink MultipeerConnectivity - Apple Developer Documentation, Developer.Apple.com, 12 April 2018, This protocol and others are used in the feature AirDrop, used for sharing both trivial-sized content like links and contact cards, and large files of any size, between Apple devices without the need for network infrastructure. Wi‑Fi Direct was meant to bring somewhat similar capabilities to other devices.

Game consoles

The Xbox One, released in 2013, supports Wi-Fi Direct.WEB,weblink Xbox One's Wi-fi Direct - An understated feature of the Xbox One?, 2013-06-24, 2013-09-30, NVIDIA's SHIELD controller uses Wi-Fi Direct to connect to compatible devices. NVIDIA claims a reduction in latency and increase in throughput over competing Bluetooth controllers.WEB,weblink Wireless Game Controller, 2014-08-03,

See also

• Digital Living Network Alliance
• FiRa Consortium
• Li-Fi
• TDLS
• Ultra-wideband
• Wireless HDMI

References

{{Reflist}}