Georgios Fortetsanakis

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This paper presents the u-map, a novel user-centric geo-database for wireless access markets that enables clients to upload information about their profile, their quality-of-experience (QoE) feedback for a service, traffic demand, network/spectrum conditions (e.g., interference, coverage), providers, and their position (e.g., GPS-based measurements) in a(More)
Traditionally customers subscribe to specific providers and are served by accessing base stations (BSs) of the network of their provider. Inevitably subscribers with relatively “high” usage pattern and data-rate requirements are subsidized by the ones with lower usage and data-rates. As the wireless technology advances, a diverse set of(More)
This work presents a novel multi-layer modelling framework for the evolution of spectrum markets of multiple spectrum/network operators that provide wireless access to users. It integrates models of the channel, mobility, user preference, network operators (providers), infrastructure deployment, user distribution, and price-adaptation mechanisms. Providers(More)
Advances in networking and regulatory changes on access and competition rules enable new network architectures, service paradigms, and partnerships, opening new opportunities for business cases. Unlike traditional cellular-based markets, new spectrum and wireless access markets are formed that have larger sizes, are more diverse, and can offer an improved(More)
This paper focuses on a comparative statistical analysis of the performance of VoIP calls under various situations, namely, during a handover and under different background traffic conditions at a wireless access point (AP). Using empirical-based measurements, it demonstrates that these network conditions exhibit distinct statistical behaviour, in terms of(More)
This paper performs a comparative analysis of the perceived quality of (unidirectional, non-interactive) VoIP calls under various wireless network conditions (e.g., handover, high traffic demand). It employs the PESQ tool, E-model and auditory tests to evaluate the impact of these network conditions on the perceived quality of VoIP calls. It also reveals(More)
—This report presents a novel game-theoretical framework to model the evolution of spectrum markets that consists of multiple spectrum/network operators that provide wireless access to users. It integrates models about the channel, mobility, user preference, network operators (providers), infrastructure deployment, user distribution, and price-adaptation(More)
—Modeling wireless access and spectrum markets is challenging due to a plethora of technological and economic aspects that affect their evolution. This work develops a modeling framework for analysing such markets using network economics, game theory, and queueing networks. The framework models the service selection of users as well as the competition and(More)
—This paper focuses on the performance of VoIP calls under various situations, namely, during a handover, under different background traffic conditions (normal and heavy traffic load/saturation conditions) at a wireless access point, and in the presence of interference. Using empirical-based measurements, we demonstrate that various network conditions(More)