This digital document is a journal article from Computers and Operations Research, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.Description: This paper presents an application we developed for France Telecom R&D to solve a difficult real-life network problem. The problem takes place in an Asynchronous Transfer Mode (ATM) network administration context and consists in plannin g demands of connection over a period of 1 year. A new demand is accepted if both bandwidth and Quality of Service (QoS) requirements are satisfied. Demands are not known prior to the assignment and must be performed on-line according to their arrival. Moreover, the acceptance or the reject of a demand must be decided within a given time of 1 min. First, we look for a route satisfying the new demand. In case of failure, we try to reroute some already accepted connections in order to satisfy this new demand. Rerouting has been modelled as a Weighted Constraint Satisfaction Problem (WCSP) and solved by VNS/LDS+CP, a hybrid method well suited for solving WCSPs in on-line contexts. Experiments show that our rerouting enables to accept an average of 67% of demands that would be rejected otherwise.
