Modeling user preferences for vertical handover in 3G-WLAN interworking environment on top of IEEE 802.11u

In a heterogeneous networking environment vertical handover decision plays a very crucial role in the overall handover process. Many parameters and techniques have been proposed in the literature for selecting a best network available at a particular instance of time. Since user satisfaction is one of the ultimate aim of vertical handover process and different users can have different preferences on the same parameter, one of the vertical handover decision parameter is User-Preference. In this paper, limiting the scope to 3G-WLAN interworking environment and using Analytic Hierarchy Process (AHP), the problem of capturing user preferences on top of IEEE 802.11u is modeled. IEEE 802.11u is the ninth amendment to IEEE 802.11-2007 standard and allows interworking of Wireless Local Area Network (WLAN) with external networks. Using the proposed model, the ranking of available networks can be done based on only user preferences. These ranking values can further be used with other parameters (e.g. bandwidth, delay, jitter etc.) to select the best network for vertical handover. We also present the results of a survey among a group of users. This survey suggests the services which 802.11u compatible WLAN service providers should consider providing to users.