Combinatorial Algorithms for the Unsplittable Flow Problem

Strongly Polynomial Algorithms for the Unsplittable Flow Problem

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...

Approximation Algorithms for Single-Source Unsplittable Flow

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 ...

Approximation Algorithms for the Unsplittable Flow Problem on Paths and Trees

We study the Unsplittable Flow Problem (UFP) and related variants, namely UFP with Bag Constraints and UFP with Rounds, on paths and trees. We provide improved constant factor approximation algorithms for all these problems under the no bottleneck assumption (NBA), which says that the maximum demand for any source-sink pair is at most the minimum capacity of any edge. We obtain these improved r...