IEEE 802.11u-2011 is an amendment to the IEEE 802.11-2007 standard to add features that improve interworking with external networks.
802.11 is a family of IEEE technical standards for mobile communication devices such as laptop computers or multi-mode phones to join a wireless local area network (WLAN) widely used in the home, public hotspots and commercial establishments.
The IEEE 802.11u standard was published on February 25, 2011.