Seamless Mobility in Heterogeneous Wireless Networks
Résumé
In next generation of wireless networks, different technologies belonging to one or more operators should be integrated to form a heterogeneous environment based on an IP core network infrastructure. This ensures user mobility and service continuity by maintaining connections when switching between various technologies and it introduces new resources and possibilities for applications. In this context, an automatic interface selection based on instantaneous and practical constraints and user preferences (Quality of Service (QoS) parameters, available resources, security, power consumption, etc) is therefore required. The different network selection and handover schemes proposed in the literature can be classified into three approaches according to who is responsible for making the handover decision: the terminal, the network or thanks to a cooperation between both of them. However, these approaches keep presenting some drawbacks; namely the problem of resources management and network load balancing whenever the selection is controlled by the mobile terminal (MT) and the problem of scalability and unknown operator's management policy whenever the selection is rather controlled by the network. In this article, first we propose a new architecture and new network selection scheme that explicitly take into account the current resource usage and the user preferences. Furthermore, our solution ensures the selection of the most suitable network for each flow while taking into consideration its expectations in terms of QoS. A feasibility study of our architecture is then triggered on a single MT by using typical scenarios and using various algorithms to evaluate their performances.