WiFi Direct Demystified
by Lim Pei Hao
06 January 2012 - WiFi Direct is a wireless standard embraced by the WiFi Alliance that allows two devices to communicate each other sans the need of an access point or hotspot.
In the conventional method or “infrastructure mode”, data transferred wirelessly between devices need a router that acts as traffic police. WiFi Direct, however, basically embeds a soft access point (Soft AP) into the WiFi Direct certified devices, allowing peer to peer communication within a short range of distance.
A common misconception that usually occurs is that people would think that WiFi Direct is the same as “ad-hoc mode”, but they are two different wireless standards. WiFi Direct may function like an “ad-hoc mode” which involves peer to peer communication, but it has the advantage in terms of security compared to the traditional “ad-hoc mode”.
Furthermore, WiFi Direct uses the WiFi 802.11 b/g/n bands, where users can expect a bigger radius and faster transfer speed compared to Bluetooth technology. This allows data sharing such as sending files between two devices or streaming a video to another device to be more convenient.
The beauty of WiFi Direct is its ability to make one-to-one or one-to-many device connections at the same time. Connection can be also established between a WiFi certified device and a legacy WiFi device.
In the Android platform, devices with Android 2.3 or Gingerbread and below support WiFi Direct only if the manufacturer decides to add on the feature and with some code modification over the Android operating system (OS). The LG Optimus Black, Samsung Galaxy S and Galaxy S II are examples of existing smartphones in the market that support WiFi Direct. Some Sony BRAVIA LED TVs with WiFi Direct allow media sharing via Sony Ericsson Xperia smartphones.
Google later added the WiFi Direct support in their latest Android 4.0 or Ice Cream Sandwich OS. This makes the Samsung Galaxy Nexus the first Android phone that offers native WiFi Direct without any tethering from the manufacturer.
Ultimately, WiFi Direct would be a good alternative for replacing Bluetooth. However, incompatibility issues arise when there is a lack of universal standards for the WiFi Direct specification, making it less appealing for manufacturers to adopt the technology.