Comparing multicast and newscast communication in evolving agent societies

This paper investigates the effects of two different communication protocols within an artificial society, where communication and cooperation is necessary to survive. Communication in our system is not a hard-coded behavior, rather it is an evolvable feature. The two protocols we consider differ significantly. Using the first approach, individuals multicast messages that can be received by any individual. In the second approach, based on the so-called newscast computing model, individuals send a message to their list of "friends" only, where this list is frequently updated. These protocols are compared experimentally by their effects on population dynamics and the evolution of communicativeness. The results provide new insights into the niche of newscast-based communication protocols: we identify two essential processes (information being spread and information loosing its value) and consider the ratio of the speeds of these processes as a basic indicator for communication success.