How can Wi-Fi Ad Hoc mode be enhanced?
The original 802.11 standard defined two modes of operation:
1) Ad hoc mode, where stations communicate directly with each other; and
2) Infrastructure mode, where all stations communicate through an access point which is attached to a distribution network like the Internet.
Although ad hoc mode is widely supported by Wi-Fi products, few businesses use it and some actually ban it. Ad hoc mode is most often used by individuals – for example, to copy shared files from one laptop to another in situations where no AP exists. However, the most common use is probably when a station attempts to connect to another station unintentionally advertising the SSID "Free Public WiFi" – even though neither station is actually connected to the Internet.
To provide an easier, more secure peer-to-peer communication alternative, the Wi-Fi Alliance recently defined Wi-Fi Direct. Even though it works very differently under the covers, Wi-Fi Direct effectively replaces ad hoc mode. For example, Wi-Fi Direct enables as-needed file sharing between two laptops – or between a camera and a laptop, or a laptop and a projector, etc. Just about any situation where you might have used ad hoc mode in the past, you'll probably be able to use Wi-Fi Direct instead.
What makes Wi-Fi Direct better? Unlike ad hoc mode, Wi-Fi Direct connections are inherently secure. When two devices decide to communicate with Wi-Fi Direct, they use Wi-Fi Protected Setup to turn on WPA2 security with an auto-generated key. Better yet, there's no configuration, because Wi-Fi Direct devices locate other nearby devices that offer desired services. Users don't have to figure out how devices will get IP addresses or route traffic or what Wi-Fi channels will be used. Those details are hidden from users, similar to the way that plug-and-play printers and media servers are found in wired networks today. To learn about Wi-Fi Direct, visit.
This was first published in April 2011