This book extensively examines the next generation wireless local area networks. The past two decades have observed startling developments in wireless LAN technologies that were triggered by its expanding popularity on the home front because of ease of installation, and in commercial complexes granting wireless access to their customers. This book talks about some of the recent advancement status of wireless LAN, encompassing the topics on physical layer, MAC layer, QoS and systems. It offers an opportunity for both practitioners and researchers to examine the problems that emerge in the rapidly advancing technologies in wireless LAN.