Infrastructure and device-to-device cellular data offloading

Abstract

This thesis addresses the overload problem of the Wireless Internet service Providers' (WISP) network. The growth of mobile broadband subscription has been leading several bottlenecks to WISPs, such as, bandwidth availability and resource sharing over a single cellular cell. WISPs can move o data trac from its infrastructure by deploying small cells, such as femtocells, to public WiFi networks or, more recently, todevice-to-device opportunistic networks. This work evaluates the feasibility to ooad mobile data trac using WiFi hotspots, proposes a framework to opportunistic data ooading and incentive mechanisms to encourage users cooperation. We mapped 3G and WiFi coverage through several bus routes in Paris in order to evaluate how users and WISPs can benet from the existing infrastructure. Our results indicate that the deployed WISPs access points can ooad part of the datatrac, however restrictions such as association time and the authentication process may reduce the amount of ooaded data.We propose a multi-criteria decision-making framework, called OppLite, to ooad data from 3G networks using opportunistic device-to-device communications. Tracedriven simulations showed that opportunistic mobile ooading can expand coverage and network eciency, ooading up to 36% of data in certain scenarios. Thus, the eectiveness of opportunistic mobile ooading depends mainly of the delay toleranceof the applications and whether the user cooperates. Since opportunistic ooading depends on the user's willingness to oer his/herresources to others, we propose a message-based incentive mechanism that builds a reputation rank based on the source of messages received by the forwarding nodes, called MINEIRO. The network supports up to 60% of nodes with selsh behavior without performance degradation in a random mobility scenario. After this threshold, MINEIRO kept the delivery rate and the delay constant. Meanwhile, in a scenario with social-based mobility, selsh behavior degrades the network performance quickly.