Time-dependent combined network design and routing optimization

In today´s communication networks, distributed control functions such as routing inherit their design driven by processing capacity and memory consumption. Henceforth, the routing protocol decision process (distributed and online) remains still decoupled from the routing optimization process (centralized and offline). Distributed optimization does not take into account the distributed nature of the online routing decision making process because distributed optimization is not decomposed along the same dimensions as the routing decision making process. The challenge becomes thus how to modify the routing decision process to include optimization objectives and how to make the optimization problem aware of the distributed nature of the online routing decision process under dynamic conditions. As a first evolution in that direction, we propose a new combined optimization model that integrates network design decisions and routing decisions, with time-dependent demands. As part of our main contribution, the proposed model keeps in sight the need for a distributed routing function, through the use of scalable routing tables. We also put our work in the perspective of a fully distributed, decomposed optimization setting.