Diagnosability of faults in discrete event systems modeled with Petri nets can be assessed either via graph-based techniques (also called diagnoser, verifier/twin-plant based techniques), or via the solution of optimization problems. The approaches that belong to the former class are based on the analysis of the net reachability or coverability graphs (or of a more compact version of them). The latter approach exploits the mathematical representation of the net itself to specify and solve optimization problems, which are usually expressed as integer linear programming (ILP) problems. In this paper we exploit the railway Petri net model originally proposed in [16], and extended in [14] to be used as a benchmark for diagnosability analysis, to assess the efficiency of the approach based on the solution of ILP problems proposed in [3]. In order to show the effectiveness of the proposed technique, a comparison with a graph-based approach for analyzing diagnosability is also presented.