Eventually the ants abandon other avenues of exploration in favor of the one tried and tested route. When confronted with an obstacle on the preferred path, the ants quickly switch to the next most efficient line to the food. ACO software solves travel problems in much the same way. To find the shortest distances between a large number of destinations, the program repeatedly issues a set of virtual ants, or agents, which randomly visit all the destinations on their electronic road map and lay virtual pheromone trails. Other agents can follow this marked path, and eventually the best rout is mapped out.
Drivers use the software to determine alternative routes around pile-ups or roadworks.
Yet ant-inspired software isn't only useful in deploying a fleet of trucks. DaimlerChrysler recently tested how ACO software might improve the production processes at its body paint conveyor belts, while at Unilever ant algorithms have already helped identify the most efficient allocation of mixing and storage tanks and packaging machines. Web traffic blocked by a broken down server could be speedily redirected if packets encountering such an obstacle left a data-trail on their way around it. Succeeding messages could then follow them ant-style. For all those who use ACO software, it seems, chances are good that traffic jams will no longer be an obstacle, either on the information highway or on real-life autobahns.