A note on iterated rounding for the survivable network design problem

Abstract

© Chandra Chekuri and Thapanapong Rukkanchanunt. In this note we consider the survivable network design problem (SNDP) in undirected graphs. We make two contributions. The first is a new counting argument in the iterated rounding based 2-approximation for edge-connectivity SNDP (EC-SNDP) originally due to Jain [10]. The second contribution is to make some connections between hypergraphic version of SNDP (Hypergraph-SNDP) introduced in [17] and edge and node-weighted versions of EC-SNDP and element-connectivity SNDP (Elem-SNDP). One useful consequence is a 2-approximation for Elem-SNDP that avoids the use of set-pair based relaxation and analysis.