11 - Wireless LANs

Abstract

This chapter provides an insight into wireless local area networks (WLAN) technologies. The most important advantage of wireless networking is mobility. The only requirement is that the wireless users should be within the specified range of the base station. When the wireless station traverses from its home subnet to the second subnet, it attaches itself to the network employing the usual procedure. It gets connected to an access point and requests for an Internet Protocol (IP) address using dynamic host configuration protocol (DHCP). Wireless stations using Mobile IP software can maintain their connection state by registering with the home agent. The mobile station can receive packets for the mobile station, verify its registration tables, and then transmit packets to the mobile station at its present location. The other concepts discussed in this chapter are open systems interconnection (OSI) layer implementation, medium access control, system components, basic service set and extended service set, ad hoc and infrastructure modes. The security issues concerning wireless networks are also discussed. Finally, the chapter highlights the differences between a WLAN and wireless personal area network (WPAN) and discusses the Bluetooth/IEEE 802.15 standards.