Title
A Comparison of Optimal Methods for Local Access Uncapacitated Network Design
Abstract
We compare some optimal methods addressed to a problem of local access network design. We see this problem arising in telecommunication as a flow extension of the Steiner problem in directed graphs, thus including as particular cases some alternative approaches based on the spanning tree problem. We work with two equivalent flow formulations for the problem, the first referring to a single commodity and the second being a multicommodity flow model. The objective in both cases is the cost minimization of the sum of the fixed (structural) and variable (operational) costs of all the arcs composing an arborescence that links the origin node (switching center) to every demand node. The weak single commodity flow formulation is solved by a branch-and-bound strategy that applies Lagrangian relaxation for computing the bounds. The strong multicommodity flow model is solved by a branch-and-cut algorithm and by Benders decomposition. The use of a linear programming solver to address both the single commodity and the multicommodity models has also been investigated. Our experience suggests that a certain number of these modeling and solution strategies can be applied to the frequently occurring problems where basic optimal solutions to the linear program are automatically integral, so it also solves the combinatorial optimization problem right away. On the other hand, our main conclusion is that a well tailored Benders partitioning approach emerges as a robust method to cope with that fabricated cases where the linear programming relaxation exhibits a gap between the continuous and the integral optimal values.
Year
DOI
Venue
2001
10.1023/A:1014569927266
Annals OR
Keywords
Field
DocType
network design,Benders decomposition,branch-and-bound,branch-and-cut
Branch and bound,Mathematical optimization,Steiner tree problem,Linear programming,Lagrangian relaxation,Solver,Multi-commodity flow problem,Linear programming relaxation,Minimum-cost flow problem,Mathematics
Journal
Volume
Issue
ISSN
106
1-4
1572-9338
Citations 
PageRank 
References 
8
0.65
34
Authors
2
Name
Order
Citations
PageRank
C. D. Randazzo1191.72
H. P. Luna2557.39