Table of Contents
ISRN Communications and Networking
Volume 2012, Article ID 914953, 9 pages
Research Article

Optimizing Virtual Private Network Design Using a New Heuristic Optimization Method

Erik Jonsson School of Engineering and Computer Science, University of Texas at Dallas, Richardson, TX 75083, USA

Received 21 March 2012; Accepted 19 April 2012

Academic Editors: A. Maaref, C. Pomalaza-Ráez, and A. Zanella

Copyright © 2012 Hongbing Lian and András Faragó. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


In virtual private network (VPN) design, the goal is to implement a logical overlay network on top of a given physical network. We model the traffic loss caused by blocking not only on isolated links, but also at the network level. A successful model that captures the considered network level phenomenon is the well-known reduced load approximation. We consider here the optimization problem of maximizing the carried traffic in the VPN. This is a hard optimization problem. To deal with it, we introduce a heuristic local search technique called landscape smoothing search (LSS). This study first describes the LSS heuristic. Then we introduce an improved version called fast landscape smoothing search (FLSS) method to overcome the slow search speed when the objective function calculation is very time consuming. We apply FLSS to VPN design optimization and compare with well-known optimization methods such as simulated annealing (SA) and genetic algorithm (GA). The FLSS achieves better results for this VPN design optimization problem than simulated annealing and genetic algorithm.