Article

Mobile Data Offloading through Opportunistic Communications and Social Participation

University of Maryland, College Park
IEEE Transactions on Mobile Computing (Impact Factor: 2.54). 06/2012; 11(5):821 - 834. DOI: 10.1109/TMC.2011.101
Source: IEEE Xplore

ABSTRACT

3G networks are currently overloaded, due to the increasing popularity of various applications for smartphones. Offloading mobile data traffic through opportunistic communications is a promising solution to partially solve this problem, because there is almost no monetary cost for it. We propose to exploit opportunistic communications to facilitate information dissemination in the emerging Mobile Social Networks (MoSoNets) and thus reduce the amount of mobile data traffic. As a case study, we investigate the target-set selection problem for information delivery. In particular, we study how to select the target set with only k users, such that we can minimize the mobile data traffic over cellular networks. We propose three algorithms, called Greedy, Heuristic, and Random, for this problem and evaluate their performance through an extensive trace-driven simulation study. Our simulation results verify the efficiency of these algorithms for both synthetic and real-world mobility traces. For example, the Heuristic algorithm can offload mobile data traffic by up to 73.66 percent for a real-world mobility trace. Moreover, to investigate the feasibility of opportunistic communications for mobile phones, we implement a proof-of-concept prototype, called Opp-off, on Nokia N900 smartphones, which utilizes their Bluetooth interface for device/service discovery and content transfer.

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    • ". Offloading cellular traffic to a cooperative opportunistic VANET tunistic networks has been investigated, to the best of our knowledge, all existing studies only focus on the scenario that the content can be transmitted by one contact (e.g., [3]–[6], [8], [12], [18]). In practice, bulk data, e.g., a podcast, can hardly be completely forwarded from one vehicle to another during their limited contact duration. "
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    • "A first class of offloading techniques based on opportunistic networks is based on approaches in which the dissemination controller has to collect information about nodes' contact rates in order to come up with the best set of nodes to trigger the dissemination of contents in the opportunistic network . To the best of our knowledge, Han et al. [39] (then subsequently extended in [40]) were the first to exploit opportunistic communications to alleviate data traffic in the cellular network. In their pioneering work they propose and evaluate three algorithms, i.e. "
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    • "This motivates us to introduce a finer model of radio resource consumption with respect to those used in the literature. While this is well understood in the literature on physical aspects of cellular communications, existing proposals for opportunistic offloading do not consider heterogeneous channel conditions , assuming that delivering a given amount of data (i.e., a fixed size packet) to different users has always the same cost for the operator [13] [17]. Such an assumption does not hold in reality, as resource consumption varies according to the channel condition experienced by each user. "
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