Leon Rothkrantz, Knowledge Based Systems,
Technical Informatics Department, Delft University of Technology, The
In the paper we describe a novel way to route data within a packet switched network. It is implemented in a new telecommunication service. In that service the destinations from the cover page of the received faxes will be extracted automatically and the fax will be routed to its final destination via a special network of nodes in the normal telephone network. The network can consist of all kinds of links: leased lines, satelite links, dial-up modem connections and of course the internet. The routing algorithm routes data over the network from one end-point to another end-point via the best route. Two of the requirements of this service are a high availability and a high degree of flexibility. To fullfil these requirements, the routing algorithm should be robuust and flexible as well. The routing algorithm for this packet switched network is based on the natural behaviour of ants. The idea to use emergent behaviour for various optimisation problems was introduced by Marco Dorigo. We used the same ideas to route calls in a circuit switched telephone network [R. Schoonderwoerd e.o]. Two agent algorithms based on the emergent behaviour of ants have been implemented in software. The first algorithm is similar to the one used for the switched telephone network. The trip times is used as a cost function instead of the spare capacity of nodes. In the second algorithm is based on forward and backward agents. The experiments that have been conducted show that the agent algorithms can do a very good job of routing packets in a packet switched network.