@phdthesis{2011mehani_adaptive_use_mobile_networks_phd, abstract = {With the widespread availability of multiple wireless network technologies, mobile com- puting devices can benefit from almost uninterrupted connectivity by changing network attachments as they move. This however raises the problem of the selection method to be used for the choice of the wireless networks to associate with, in order to provide the best performance. Moreover, mobility events may result in poor application quality, due to either a disruption in connectivity during the handover or the heterogeneity of the charac- teristic of different access networks. To address these problems, this thesis introduces and studies all three elements (observation, decision, action) of a control framework to enable better use of available network resources. We first show that a decision mechanism which directly considers the relevant user- and application-centric metrics is more appropriate than using the common network metrics- based indirect approach. This mechanism is used to control the entire network stack of the mobile node in a coordinated way, rather than individual components, to avoid potentially conflicting combinations. Our results indicate that, by exploiting the flexibility of application parameters, it is possible to maintain high application quality while reducing both the power consumption and access price. We then introduce a mobility-aware extension to the {TCP}-Friendly Rate Control mechan- ism ({TFRC}), as an action element, to address the disruption in connectivity resulting from the mobility events. We propose to suspend the transmission before disconnections and to probe the network after reconnections. Simulations demonstrate how this enables faster recovery after disconnected periods as well as a significantly improved adaptation to the newly available network conditions. When used with the Datagram Congestion Control Protocol ({DCCP}), experiments show that it provides better support for real-time applica- tions for which the user-perceived quality is very dependent on the immediate transmission rate. Finally, we present an experimental process to evaluate the {OMF} Measurement Library ({OML}), a lightweight instrumentation and reporting tool which we propose to use as the observation element of our framework. We show that this library does not significantly impact the performance of the instrumented applications, while accurately reporting the observed metrics.}, address = {Paris, France / Sydney, Australia}, author = {Mehani, Olivier}, day = {14}, howpublished = {French title ``Contributions aux m\'{e}canismes de r\'{e}seau pour un usage adaptatif des ressources mobiles''}, keywords = {analysis, cross-layer, dccp, evaluation, flowdistribution, imara, inria, ipv6, lara, mcoa, minesparistech, minizinc, mipv6, mobility, network, networkresearchgroup, nicta, ns-2, oliviermehani, oml, phd, qoe, simulation, stack, tfrc, transport, unsw}, month = dec, school = {Mines ParisTech / University of New South Wales}, title = {Contributions to Mechanisms for Adaptive Use of Mobile Network Resources}, url = {http://olivier.mehani.name/publications/2011mehani\_adaptive\_use\_mobile\_networks\_phd.pdf}, year = {2011} }