Defining architecture and key issues towards WLAN roaming

Low deployment costs and high demand for wireless access have led to rapid deployments of public WLAN hotspot services by many providers, including startups and telecom operators. As the number of different WLAN operators in a certain geographical region is getting higher, interworking problems arising. Operators cannot reach all the potential customers and customers cannot access their services in all WLANs in the area. The solution to all these problems is "roaming". In this paper, we discuss the issue of WLAN roaming (between various operators in the same geographical area) focusing on IEEE 802.11b Standard. We present the public WLAN roaming architecture provided by Wi-Fi Alliance and note the main security issues and forecasted revenues coming out of the WLAN roaming. We end up by briefly mentioning the WLAN/Cellular interworking models and their impact on the WLAN roaming 'market'.