Network discovery and user preferences for network selection in 3G-WLAN interworking environment

In a heterogeneous networking environment vertical handover decision plays a very crucial role in the overall handover process as wrongly selected network spoils the overall purpose of Always Best Connected (ABC). For it many decision models, based on diverse parameters and techniques, have been proposed. In this paper, following two requirements which most of such models require are emphasized: a) Network information other than that available in the corresponding network advertising frame to get the values of the decision parameters considered and b) User Preferences because it is the user satisfaction which is one of the ultimate aim of vertical handover process and different users can have different preferences on the same parameter. It is shown that how additional information can be stuffed in the Information Element´s LENGTH field of 802.11 compatible beacon frame. Also, capturing user preferences is modeled primarily on the parameters derived from the fields added by IEEE 802.11u to the beacon frame. The proposed technique for it, called Analytic Hierarchy Process (AHP), is also made more effective by measuring its criticisms.