Improving user privacy with firewall techniques on the wireless LAN access point

Wireless Local Area Networks (WLANs) for public access need to provide privacy between users and also ensure correct charging where access is based on payment. However, by design, conventional LANs and WLANs provide direct, unmediated communications between networked devices at the link layer. The paper presents a method to allow networked client devices to communicate with a network comprising routers and other servers while preventing unmediated communication between the clients on the wireless network. An advantage of the method is that it can be implemented entirely within the WLAN access point as a configurable forwarding policy database. No changes are needed to the WLAN client software or the routers and servers and the communication remains completely within the scope of existing industry standards.