Project : ares

Section: Scientific Foundations

Hybrid networks modelling

Participants : Alexandre Caminada, Jean-Marie Gorce, Isabelle Guérin Lassous, Jialiang Lu, Philippe Mary, Pierre-François Morlat, Guillaume de la Roche, Katia Runser, Fabrice Valois, Guillaume Villemaud.

This scientific axis aims to propose a formal framework for the study and the evaluation of hybrid networks as defined in Section 2. The high complexity of such networks makes necessary the use of both a wide panel of different technics and several concepts of mobility.

While several solutions have been already proposed for some aspects of hybrid networks, the combination of all aspects is still challenging. Thus, adapting usual techniques used in conventional networks to the hybrid specificity, ensuring the scalability, and finding solutions as global as possible are very attractive goals. Both require a formal evaluation framework.

Models for hybrid networks have two goals: to give a better understanding of the behavior of these networks and to provide a framework for protocols design. Therefore, such models should be both simple, for tractability, and realistic, for efficiency. Finding a right balance between these antinomic requirements entails a careful identification of all the relevant parameters.

Modelling hybrid networks may be performed at different levels. It is obvious that hybrid networks aim to gather simultaneously several radio networks including different medium access techniques, mobile equipements having different mobility profiles, different traffic flows and network entities having different capacities. Taking into account all of these specific aspects is untractable, and in the modelling task it is firstly aimed to extract the set of relevant characteristics of hybrid networks. Moreover, it is crucial to work not only on usual radio interfaces but also on advanced technologies in order to anticipate future capacities. Modelling the interactions between the network layers (physical/data link, data link/network) is challenging as well as taking into account the dynamic feature of these networks. Finally, a framework for the performance evaluation of these networks should be proposed. This framework should integrate both realistic characteristics of environment and well-defined mobility and traffic models.