Dual-Based Approximation Algorithms for Cut-Based Network Connectivity Problems

Dual-Fitting Approximation Algorithms for Network Connectivity Problems

We consider the NP-complete network connectivity problem of Dual Power Assignment (DPA). This models an ad hoc networks where each node can either operate at high or low power. The goal is to produce a minimum power strongly connected network. We give a Dual-Fitting algorithm to DPA with a 3/2-approximation ratio, improving the previous best know approximation of 11/7 ≈ 1.57. Another standard n...

Algorithms for Graph Connectivity and Cut Problems - Connectivity Augmentation, All-Pairs Minimum Cut, and Cut-Based Clustering

Approximation algorithms for network problems

Graph Algorithms for Network Connectivity Problems

This paper surveys the recent progress on the graph algorithms for solving network connectivity problems such as the extreme set problem, the cactus representation problem, the edge-connectivity augmentation problem and the source location problem. In particular, we show that efficient algorithms for these problems can be designed based on maximum adjacency orderings.

Approximation Algorithms for Feasible Cut and Multicut Problems

Let G = (V; E) be an undirected graph with a capacity function u : E!< + and let S 1 ; S 2 ; : : : ; S k be k commodities, where each S i consists of a pair of nodes. A set X of nodes is called feasible if it contains no S i , and a cut (X; X) is called feasible if X is feasible. Several optimization problems on feasible cuts are shown to be NP-hard. A 2-approximation algorithm for the minimum-...