Approximation Algorithms for Single-Source Unsplittable Flow

Approximation Algorithms for Single-Source Unsplittable Flow

Experimental Evaluation of Approximation Algorithms for Single-Source Unsplittable Flow

In the single-source unsplittable ow problem, we are given a network G; a source vertex s and k commodities with sinks ti and real-valued demands i; 1 i k: We seek to route the demand i of each commodity i along a single s-ti ow path, so that the total ow routed across any edge e is bounded by the edge capacity ce: This NP-hard problem combines the diiculty of bin-packing with routing through a...

Single-Source Unsplittable Flow

The max-ow min-cut theorem of Ford and Fulkerson is based on an even more foundational result, namely Menger's theorem on graph connectivity. Menger's theorem provides a good characterization for the following single{source disjoint paths problem: given a graph G, with a source vertex s and terminals t 1 ; : : :; t k , decide whether there exist edge{disjoint s-t i paths, for i = 1; : : :; k. W...

Improved Approximation Algorithms for Unsplittable Flow Problems

In the single-source unsplittable ow problem we are given a graph G; a source vertex s and a set of sinks t 1 ; : : :; t k with associated demands. We seek a single s-t i ow path for each commodity i so that the demands are satissed and the total ow routed across any edge e is bounded by its capacity c e : The problem is an NP-hard variant of max ow and a generalization of single-source edge-di...

On the Single-Source Unsplittable Flow Problem

If the necessary cut condition is satisfied, we show how to compute an unsplittable flow satisfying the demands such that the total flow through any edge exceeds its capacity by at most the maximum demand. For graphs in which all capacities are at least the maximum demand, we therefore obtain an unsplittable flow with congestion at most 2, and this result is best possible. Furthermore, we show ...