Multi-RAT traffic offloading solutions for the bandwidth crunch problem

Spurred by the increasing demand for mobile broadband services and the growing number of devices supporting multiple radio access technologies (e.g., cellular, WiMAX, Wi-Fi, Bluetooth), much research is being done to improve the user experience while addressing issues related to network efficiency, congestion, interference, and cost to operators, service providers, manufacturers, and consumers alike. Standards bodies, industry players, and academia have been considering a wide range of inter-technology convergence solutions to address these issues. The solutions range from simple switching from one radio network to a “better” one, to maintaining individual application flows on multiple radio networks simultaneously and switching them dynamically as desired. More advanced solutions go one step further and aggregate the bandwidth across multiple simultaneous radio connections, thus increasing the data rates available for the applications. While the above solutions provide relief to the bandwidth crunch problem over the radio interface, different techniques are suitable to solve the loading and congestion problem over the `transport network' of the Mobile Network Operators (MNOs). These include selective IP traffic offload techniques for the Core Network, and FemtoCell solutions for the Radio Access Network. In addition, FemtoCells also enable local routing of IP traffic, further reducing network load. In this paper, we shall present an overview of related standardization activities in IETF, IEEE and 3GPP, while addressing some some innovative technical solutions for residential and enterprise scenarios.