Nos visita Jannik Matuschke, TU Munich.

En el marco de los Seminarios AGCOorganizados por Núcleo Milenio Información y Coordinación en Redes el profesor Matuschke dictará la charla ” Título: The Complexity of Computing a Robust Flow”. Esta actividad se llevará a cabo el día miércoles 23 de agosto a las 14:30 horas en  República 779 B, Sala 3er Piso.

Abstract:
Robust network flows are a concept for dealing with uncertainty and unforeseen failures in the network infrastructure. One of the most basic models is the Maximum Robust Flow Problem: Given a network and an integer k, the task is to find a path flow of maximum robust value, i.e., the guaranteed value of surviving flow after removal of any k arcs in the network. The complexity of this problem appeared to have been settled almost a decade ago: Aneja et al. (2001) showed that the problem can be solved efficiently when k = 1, while an article by Du and Chandrasekaran (2007) established that the problem is NP-hard for any constant value of k larger than 1.

We point to a flaw in the proof of the latter result, leaving the complexity for constant k open once again. For the case that k is not bounded by a constant, we present a new hardness proof, establishing that the problem is strongly NP-hard, even when only two different capacity values occur and the number of paths is polynomial in the size of the input. We further show that computing optimal integral solutions is already NP-hard for k = 2 (whereas for k=1, an efficient algorithm is known) and give a positive result for the case that capacities are in {1, 2}.

This is joint work with Yann Disser (TU Darmstadt).

Más información se encuentra en la página del seminario https://www.dii.uchile.cl/acgo/seminar-acgo/.