Cellular Traffic Offloading through WiFi Networks

Abstract

Abstract-Cellular networks are currently facing the challenges of mobile data explosion. High-end mobile phones and laptops double their mobile data traffic every year and this trend is expected to continue given the rapid development of mobile social applications. It is imperative that novel architectures be developed to handle such voluminous mobile data. In this paper, we propose and evaluate an integrated architecture exploiting the opportunistic networking paradigm to migrate data traffic from cellular networks to metropolitan WiFi access points (APs). To quantify the benefits of deploying such an architecture, we consider the case of bulk file transfer and video streaming over 3G networks and simulate data delivery using real mobility data set of 500 taxis in an urban area. We are the first to quantitatively evaluate the gains of citywide WiFi offloading using large scale real traces. Our results give the numbers of APs needed for different requirements of quality of service for data delivery in large metropolitan area. We show that even with a sparse WiFi network the delivery performance can be significantly improved. This effort serves as an important feasibility study and provides guidelines for operators to evaluate the possibility and cost of this solution.

Vehicular WiFi offloading: Challenges and solutions

“…However, such interworking architectures rely on the evolution of mobile access networks with redesigned protocols. Based on off-the-shelf radio access technologies, there have been several proposed WiFi offloading frameworks in the literature [11,7,14,15,16].…”

“…In [11], a non-coupling architecture, called Metropolitan Advanced Delivery Network (MADNet), is proposed for offloading bulk data and video streaming through metropolitan WiFi networks. MADNet, designed as a middleware between the application and physical layer, uses cellular networks to do signaling such as the transfer of users' service requests and status information, and uses both cellular and WiFi networks to transmit data.…”

“…Therefore, a well-planed WiFi deployment can offer a good offloading performance at a low cost. The WiFi deployment strategies considering the popularity of locations are proposed and evaluated in [11] and [19]. The main idea is to deploy WiFi APs at locations with high popularity, i.e., visited by users with high frequency.…”

“…The main idea is to deploy WiFi APs at locations with high popularity, i.e., visited by users with high frequency. Results from [11] show that deploying several hundred of APs at the popular sites of the investigated 313.83 km 2 area can efficiently offload half of the cellular traffic. It is also pointed out in [22] that the mostly visited places are not definitely the places where the heaviest data traffic is generated.…”

“…By delivering data originally targeted for cellular networks by WiFi, which is referred to as WiFi offloading, the congestion of cellular networks can be alleviated. WiFi offloading has been extensively studied for stationary or slow moving users 2 [9,8,10,11]. It is shown that around 65% of the cellular traffic can be offloaded by merely using the most straightforward way of simply switching the IP connection from the cellular network to WiFi when the WiFi connectivity is available (on-the-spot offloading).…”