A Rent-Seeking Framework for Multipath TCP

Network utility maximization (NUM) for Multipath TCP (MPTCP) is a challenging task, since there is no well-defined utility function for MPTCP [6]. In this paper, we identify the conditions under which we can use Kelly's NUM mechanism, and explicitly compute the equilibrium. We obtain this equilibrium by using Tullock's rent-seeking framework from game theory to define a utility function for MPTCP. This approach allows us to design MPTCP algorithms with common delay and/or loss constraints at the subflow level. Furthermore, this utility function has diagonal strict concavity, which guarantees a globally unique (normalized) equilibrium.

Filters for Social Media Timelines: Models, Biases, Fairness and Implications

Social media have a significant impact, on the lifestyle, behaviour and opinion of billions of users. To handle the flow of information between its members, social media developed personalization algorithms that filter the contents that flow into users' timelines. Despite the far-reach of social media filters, such algorithms lack transparency, motivating research to understand and improve its properties. In this thesis, bridging queuing theory, caching models and network utility maximization, we propose a reproducible methodology encompassing measurements, analytical models and a utility-based method to design timelines filters. Using Facebook as a case study, our empirical results indicate that a significant bias exists and it is stronger at the topmost position of News Feed motivating the proposal of a novel and transparent fairness-based timeline design which can be controlled by users. Among the implications, we indicate the accuracy of our model to make counterfactual analysis, the capability of auditing social media and its versatility in designing multiple filters accounting for users preferences in an open and transparent way.

Beacon Transmission Rate Allocation Optimization under Synchronized P-Persistent Repetition MAC Protocol for Platooning

Platooning, which is enabled by vehicle-to-vehicle (V2V) communication, is one of the most potential frameworks in the intelligent transport system (ITS) to enhance driving safety and improve traffic capacity. In a platoon, vehicles interact with each other by broadcasting beacons via Dedicated Short Range Communication (DSRC). In this work, we explore the impact of beacon transmission rate allocation on the network utility which involves not only network performance but also traffic safety and efficiency for the vehicular ad hoc network (VANET) composing of a single platoon. An optimization problem aiming at searching for an optimal beacon transmission rate allocation for platoon management is developed based on a network utility maximization framework. Particularly, adopting a synchronized P-persistent repetition (SPR) medium access control (MAC) protocol, an optimal beacon transmission rate allocation to achieve the network utility maximization, is obtained for a platoon at a certain cruise velocity. In the simulation, the correctness of the proposed approach is validated, and its advantages over the benchmark are demonstrated by comparisons.