Y A COMPUTATIONAL STUDY OF ROUTING ALGORITHMS FOR REALISTIC TRANSPORTATION NETWORKS Rudiger R . Jacob , TSASA Kai " NMI " Nagel , TSASA Madhav V .

We carry out an experimental analysis of a number of shortest path (routing) algorithms investigated in the context of the TRANSIMS (TRansportation ANalysis and SIMulation System) project. The main focus of the paper is to study how various heuristic and exact solutions, associated data structures affected the computational performance of the software developed especially for realistic transportation networks. For this purpose we have used Dallas Ft-Worth road network with very high degree of resolution. The following general results are obtained. 1. We discuss and experimentally analyze various one-one shortest path algorithms. These include classical exact algorithms studied in the literature as well as heuristic solutions that are designed to take into account the geometric structure of the input instances. 2. We describe a number of extensions to the basic shortest path algorithm. These extensions were primarily motivated by practical problems arising in TRANSIMS and ITS (Intelligent Transportation Systems) related technologies. Extensions discussed include (i) Time dependent networks, (ii) multi-modal networks, (iii) networks with public transportation and associated schedules. Computational results are provided to empirically compare the efficiency of various algorithms. Our studies indicate that a modified Dijkstra's algorithm is computationally fast and an excellent candidate for use in various transportation planning applications as well as ITS related technologies.