Wi-Fi Aware™: A platform for proximity-based Wi-Fi® innovation
January 20, 2015 by Rolf de Vegt
In mid-2015, Wi-Fi Alliance® will launch a new certification program that is intended to set the stage for a new wave of Wi-Fi® innovation around the concept of proximity-based discovery. Wi-Fi Aware™ enables applications residing on Wi-Fi devices to discover each other when they are in proximity (range) of each other. Application discovery using Wi-Fi Aware does not require connection to a Wi-Fi network which opens the door for many new device-to-device interactions.
Four essential capabilities
Wi-Fi Aware is designed to include four essential capabilities to enable this proximity-based discovery:
- Establishment of a ‘common heartbeat’ among Wi-Fi devices, to make sure that Wi-Fi Aware devices are awake during the same time period during which discovery can take place
- A protocol that defines how applications on devices can discover similar applications on other devices that are in proximity, through ‘publish’ and ‘subscribe’ messages
- A method for application developers to create unique, short identifiers for applications
- Enablers for follow-up activity after successful discovery has taken place
The establishment of the ‘common heartbeat’ among nearby Wi-Fi Aware devices is key to make sure that continuous discovery can take place without putting undue burden on the battery of a mobile device. A Wi-Fi radio draws most of its power during the short time frames when the radio is transmitting or actively receiving, and most of the time a Wi-Fi radio is ‘asleep’ to conserve power. To make sure that Wi-Fi Aware devices wake up at the same time, the Wi-Fi Aware protocol establishes a common cadence of wake-up and sleep among Wi-Fi Aware devices in proximity. This is also known as ‘synchronization.’ The ability to establish synchronization among disparate devices that don’t need to have a common owner, brand, service provider or network is the key enabling feature of Wi-Fi Aware.
Wi-Fi Aware in action
Perhaps one of the best ways to portray the benefits of Wi-Fi Aware is through an example. Let’s take an example of a party of around 50 people. Each person brings their own mobile device (a mix of tablets and smartphones) which they use to capture pictures of each other and the party. They want to share their photos with others so they open the photo sharing application on their Wi-Fi Aware-capable mobile devices. Using the unique ID that the photo sharing app developer has assigned through its app, the Wi-Fi Aware devices are able to discover and interact with other Wi-Fi Aware devices using the same application. The specific user interaction and data transfer of the pictures is out of scope of Wi-Fi Aware and up to the application developer, but could include sharing or even collaboratively editing the photos. Application developers can also leverage Wi-Fi Aware to trigger the establishment of a Wi-Fi Direct® session to enable the picture transfer.
Other examples of use cases for Wi-Fi Aware are social gaming, team coordination, and advertisements of goods and pricing at a marketplace.
Unleashing a wave of innovation
End users typically love the spontaneous, user-controlled nature of Wi-Fi and making this additional capability available to application developers has the potential to unleash a wave on innovative applications and usages for mobile devices.
By allowing for limited data exchanges between Wi-Fi Aware devices, one could envision an environment where Wi-Fi Aware devices provide small pieces of information to other Wi-Fi Aware devices, e.g. location data, sensor readings, pricing data goods in proximity etc. Security for such information flows would be handled at the application level.
In addition to the possibility of setting up a Wi-Fi Direct session between devices after Wi-Fi Aware discovery has established a need for such a session, Wi-Fi Aware can also be used to connect to a network in infrastructure mode.
To take full advantage of the Wi-Fi Aware discovery capabilities, an application developer will need support from the OS (Operating system, e.g. IOS, Android, Windows) for their target platform. Given rapid OS upgrades cycles in the mobile device industry, it should not be long before end user can take advantage of Wi-Fi Aware capabilities.
Proximity based discovery based on geolocation and cloud-based matching is used in a number of applications in the market today, but this approach requires continuous internet connectivity, and cloud support. Although there are other technologies for direct device-to-device, proximity-based discovery already in the marketplace or under development in standards bodies, Wi-Fi is very well suited to take this capability to the mainstream. Some of the advantages that the Wi-Fi based approach offers are: robustness of the device to device link, richness of discovery information exchanges and end user-control of the applications driving discovery. Furthermore the use of unlicensed spectrum reduces the need for immediate service revenue generation.
Looking ahead, one can foresee that Wi-Fi Aware has the potential to serve as an enabling platform for bundling with other Wi-Fi capabilities - for example Wi-Fi location -to add distance estimation to proximity discovery. Other examples would include more robust “many to many” data exchanges and the use of Wi-Fi Aware for the Internet of Things.
Once Wi-Fi Alliance launches the Wi-Fi Aware program in 2015, there will be multiple chipsets in the marketplace. Activity and interest should then quickly turn to OS vendors and application developers to build on this unique platform for proximity-based Wi-Fi innovation.
Rolf de Vegt
Rolf de Vegt is an active participant in the Wi-Fi Alliance task group which defined the requirements for Wi-Fi Aware.
He has been active in the Wi-Fi industry since 2001 and has chaired several key task groups in the Wi-Fi Alliance, among which the groups that drove the development of the Wi-Fi Alliance programs for IEEE802.11n and 802.11ac technologies. He currently chairs a group that is defining the program for devices that implement the IEEE 802.11ah (Sub 1 GHz, extended range) standard and serves on the Wi-Fi Alliance Board of Directors.
Rolf is a Senior Director in the Qualcomm Atheros, Inc. subsidiary of QUALCOMM Incorporated.