Network planning with constraint programming

This paper presents a network planning application developed at THALES Research and Technology. The problem is to determine the successive evolutions to make in a GSM network so that all forecasted demands are satisfied and the global cost of investment and infrastructures maintenance is minimized. The application was modeled with a constraint solver over finite domains. The resolution algorithm was designed according to the architecture defined in EOLE project and developed with the ToOLS © (Templates of On-Line Search) library. In this framework, a search algorithm is the conjunction of four distinct components: (1) a set of heuristics to order choices, (2) a search scheme which represents a search tree, (3) a search strategy applied to a search scheme to control its complexity and (4) a temporal strategy allowing the management of time for the hybrid search algorithms. We illustrate the relevance of such a library with a quick prototyping and a resolution algorithms comparison (partial searches and hybrid algorithms).