Flow/Interface Association for multi-connectivity in heterogeneous wireless networks: e-Health case.

A heterogeneous wireless environment is composed of different radio access technologies (RATs) including IEEE standards (e.g., Wi-Fi) and 3GPP (e.g., 2G, 3G, 4G, 5G), each with different coverage and different capacity to cater for diverse service requirements. In such an environment, multiple access networks could be available for a mobile user. Each user can run multiple applications that have particular Quality of Service (QoS) requirements. Hence, it would be beneficial for a multi-interface terminal to simultaneously use two or more interfaces to gain in performance. However, using multiple networks simultaneously may consume more energy than using only one interface. Therefore, energy consumption should be considered as a criterion in the Flow/Interface Association (FIA). This paper presents a novel method called Smart Tabu Search (STS) that takes into account network conditions, the monetary cost of the network, QoS requirements of the applications, user preferences, and energy consumption of the mobile device to select the optimal FIA that achieves the best trade-off among all the considered criteria. We validate our proposal using both simulations and testbed experiments.