When trees collide: an approximation algorithm for the generalized Steiner problem on networks
When trees collide: an approximation algorithm for the generalized Steiner problem on networks
复制标题
DOI:
10.1145/103418.103437
复制
发表时间:
1991-01
期刊:
影响因子:
--
通讯作者:
Exa Corporation;Brown University;University of California-Davis
中科院分区:
文献类型:
--
作者:
Exa Corporation;Brown University;University of California-Davis
We give the first approximation algorithm for the generalized network Steiner problem, a problem in network design. An instance consists of a network with link-costs and, for each pair $\{i,j\}$ of nodes, an edge-connectivity requirement $r_{ij}$. The goal is to find a minimum-cost network using the available links and satisfying the requirements. Our algorithm outputs a solution whose cost is within $2\lceil \log_2(r+1)\rceil$ of optimal, where $r$ is the highest requirement value. In the course of proving the performance guarantee, we prove a combinatorial min-max approximate equality relating minimum-cost networks to maximum packings of certain kinds of cuts. As a consequence of the proof of this theorem, we obtain an approximation algorithm for optimally packing these cuts; we show that this algorithm has application to estimating the reliability of a probabilistic network.