Radio access considerations for data offloading with multipath TCP in cellular/WiFi networks

Mobile network operators are facing a huge increase in data traffic. Moreover, several mobile traffic forecasts indicate that this trend will continue to increase in upcoming years. Nowadays, delivering adequate quality of service is already an important challenge for operators, and it will also be in the future. A critical issue is the availability of radio resources, which are licensed, intrinsically finite and usually costly. Alternatively, there are also unlicensed bands used by technologies like WiFi, which can be exploited. Indeed, mobile network operators are already using WiFi hotspots for offloading the data traffic from their macro networks. However, available offloading strategies cannot provide continuous connectivity across different networks, due to intrinsic limitations of current Transmission Control Protocol (TCP). Multipath TCP is a recent protocol that enables more flexible connectivity by extending conventional TCP, and could be used for offloading data traffic. The aim of this paper is not to propose a new solution, but to summarize the points which should be considered on the radio access when implementing data offloading with Multipath TCP.