Dr. Ivana Ljubic
Universität Wien, Österreich

Optimization tools for last mile access networks

Improving the quality of broadband connections has become one of the main fields for investments of telecommunication providers. State-of-the-art strategies for covering the so-called last mile are based on replacing existing copper connections by fiber-optic networks. If replacing the existing copper infrastructure by fiber-optic connections is not profitable, the Fiber-To-The-Curb (FTTC) strategy is often applied: Fiber optic cables run to a cabinet serving a neighborhood, end users connect to this cabinet using the existing copper connections and switching devices are installed in these cabinets that change optical to electrical signals and vice versa. In this talk we present several mathematical models for the FTTC strategy. They cover a large number of planning aspects including the location of switching devices, assignment of customers to switchers, the incremental deployment of networks subject to coverage constraints, reliability constraints and capacity planning. Based on a thorough analysis of the problems at hand we propose efficient solution algorithms based on branch-and-cut, valid inequalities, decomposition techniques and modeling the problems at hand on extended graphs.