VirtualWiFi is a virtualization architecture for wireless LAN (WLAN) cards on Windows XP that exposes multiple virtual adapters from a single wireless adapter, one for each wireless network to which connectivity is desired. It exposes a single WLAN card to appear as multiple virtual WLAN cards to the user. The user can then configure each virtual wireless card to connect to a different wireless network. Therefore, VirtualWiFi allows a user to simultaneously connect his machine to multiple wireless networks using just one WLAN card. For example, a user connect to a guest’s machine to share files over an ad hoc network, while surf the web via another public hotspot.

VirtualWiFi interacts with the wireless card device driver at the lower end, and network protocols at the upper end. The buffering protocol is implemented in the kernel, while the switching logic is implemented as a user-level service. Virtual WiFi uses a network hopping scheme to switch the wireless card across the desired wireless networks. Switching between networks is transparent to the applications, such that the user feels she is connected to multiple wireless networks simultaneously.

The application dynamically adapts to the switching delay incurred by a wireless card, independent of the manufacturer. It also does not require manual intervention for assigning IP addresses on individual networks. Furthermore, this version of VirtualWiFi also provides users with a command-line interface to dynamically add and remove connectivity to a network.

Click here to download VirtualWiFi for Windows XP. Steps on how to use VirtualWiFi can be found here.