I'm trying to determine how routing software integrate road networks. Is there a best-practice (or standard) as to what part of the routing solution road networks are inserted specific to Vehicle Routing Problem with Time Windows (VRPTW)?
I've considered the following methods;
- Using the network first to determine shortest-path between each and every waypoint, and then performing VRPTW algorithms (large up-front cost as number of waypoints increase)
- Building initial populations first, and then using the road network only when executing cost function evaluations (as in the diagram Fig 1, Page 3 of this document)
- Executing the full VRPTW solution process and then performing shortest-path calcs only on successive waypoints defined per route sequence. (sub-optimal, road network not taken into account when evaluating route costs)
Where in the Vehicle Routing Problem (VRP) or VRPTW solving process is the road network accounted for?