<p> Mobile opportunistic networks are formed by mobile users who share similar interests and connect with one another by exploiting Bluetooth and/or WiFi connections. Such networks not only re-assemble the real-world interaction between people, but also can effectively propagate data among mobile users. This dissertation focuses on QoS-aware data query and dissemination in mobile opportunistic networks. </p><p> Firstly, I develop a distributed data query protocol for practical applications. To demonstrate the feasibility and efficiency of the proposed scheme and to gain useful empirical insights, I carry out a testbed experiment by using 25 off-the-shelf Dell Streak tablets for a period of 15 days. Moreover, extensive simulations are carried out to learn the performance trend under various network settings, which are not practical to build and evaluate in laboratories. </p><p> Secondly, the QoS-aware delivery probability (QDP) is introduced to reflect the capability of a node to deliver data to a destination within a given delay budget. Two experiments are carried out to demonstrate and evaluate the proposed QoS-aware data delivery scheme. Moreover, simulation results are obtained under DieselNet trace and power-law mobility model to study the scalability and performance trend. Our experiments and simulations demonstrate that the proposed scheme achieves efficient resource allocation according to the desired delay budget, and thus supports effective QoS provisioning. </p><p> Finally, I study the problem of delay-constrained least-cost multicast in mobile opportunistic networks. I formally formulate the problem and show it is NP-complete. Given its NP-completeness, I explore efficient and scalable heuristic solutions. I first introduce a centralized heuristic algorithm which aims to discover a tree for multicasting, in order to meet the delay constraint and achieve low communication cost. I develop a distributed online algorithm that makes an efficient decision on every transmission opportunity. I prototype the proposed distributed online multicast algorithm using Nexus tablets and conduct an experiment that involves 37 volunteers and lasts for 21 days to demonstrate its effectiveness. I also carry out simulations to evaluate the scalability of the proposed schemes.</p>
| Identifer | oai:union.ndltd.org:PROQUEST/oai:pqdtoai.proquest.com:3687694 |
| Date | 07 April 2015 |
| Creators | Liu, Yang |
| Publisher | University of Louisiana at Lafayette |
| Source Sets | ProQuest.com |
| Language | English |
| Detected Language | English |
| Type | thesis |
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