Wireless Fidelity (WiFi), Worldwide Interoperability for

he vision of Future Internet (FI) has created great expectations for the business players and a great area for research in the information, telecommunication and networking research community. The increase of user traffic demand, the numerous and QoS-pretentious applica-tions and services, as well as the evolving and emerging busi-ness models, are envisaged characteristics of the FI. A key part of this vision lies in the evolution of the wireless network-ing in order to enable users to be always-on, always-connected in an ever growing environment; in particular, the number of network nodes in the field increases exponentially and fur-thermore the overall trend is to deploy a large number of het-erogeneous systems. “Heterogeneity ” is being addressed in terms of distinct Radio Access Technologies (RATs), such a