We investigate the concept of artificial societies and identify a number of separate classes of such societies. These are compared in terms of openness, flexibility, stability, and trustfulness. The two most obvious types of artificial societies are the open societies, where there are no restrictions for joining the society, and the closed societies, where it is impossible for an "external agent" to join the society. We argue that whereas open societies supports openness and flexibility, closed societies support stability and trustfulness.

Several characteristics distinguish today's complex software systems from "traditional" ones. Examples in different areas show that these characteristics, already the focus of agent-oriented software engineering research, influence many application domains. These characteristics will impact how software systems are modeled and engineered.

In this paper, we identify and analyze a set of characteristics that increasingly distinguish today's complex software systems from "traditional" ones. Several examples in different areas show that these characteristics are not limited to a few application domains but are widespread. Then, we discuss how these characteristics are likely to impact dramatically the very way software systems are modeled and engineered. In particular, we appear to be on the edge of a radical shift of paradigm, about to change our very attitudes in software systems modeling and engineering. Keywords: Distributed Systems, Design Paradigms, Multiagent Systems. To be published in: The Knowledge Engineering Review Corresponding Author: Franco Zambonelli 2 1

This paper describes the peculiar behavior observed in a class of cellular automata that we have defined as dissipative, i.e., cellular automata that are open and makes it possible for the environment to influence their evolution. Peculiar in the dynamic evolution of this class of cellular automata is that stable macro-level spatial structures emerge from local interactions among cells, a behavior that does not emerge when the cellular automaton is closed, i.e., when the state of a cell is not influenced by the external world. Moreover, we observed that Dissipative Cellular Automata (DCA) exhibit a behavior very similar to that of dissipative structures, as macro-level spatial structures emerge as soon as the external perturbation exceeds a threshold value and it stays below the "turbulence" limit. Finally, we discuss possible relations of the performed experiments with the area of open distributed computing, and in particular of agent-based distributed computing.

In the near future, billions of entities will be connected to each other through the Internet. The current trend is that an increasingly number of entities, from smart personal devices to legacy databases, are controlled by software agents. Such agents often also posses a large amount of information about both the entity and its owner. Thus, a likely scenario is that the Internet will be populated by millions of information agents, all potentially able to communicate with each other. Unfortunately, we cannot assume that these agents are benevolent and are willing to cooperate in an altruistic fashion. As the amount of money transferred via the Internet is rapidly increasing caused by the breakthrough of e-commerce, we should actually expect a similar increase in the number of malicious agents. Another aspect that contributes to the complexity of agent interaction on the Internet is a desired openness, making it difficult to engineer agent societies in a top-down manner. Rather, we will here investigate the prerequisites necessary to form stable and trustworthy societies of information agents, and discuss some open problems and methodologies for studying them. The general conclusion is that more research is needed that takes into account the presence of malicious agents.

Abstract. This paper describes the behavior observed in a class of cellular automata that we have defined as “dissipative”, i.e., cellular automata for which the external environment can somehow inject “energy ” to dynamically influence the evolution of the automata. In this class of cellular automata, we have observed that stable macro-level global structures emerge from local interactions among cells. Since dissipative cellular automata express characteristics strongly resembling those of open multi-agent systems, we expect that similar sorts of macro-level behaviors are likely to emerge in multi-agent systems and need to be studied, controlled, and possibly fruitfully exploited. A preliminary set of experiments reporting two ways of indirectly controlling the behavior of DCA are reported and discussed w.r.t. the possibility of applying similar sort of indirect control on large multi-agent systems. 1

Mass customization manufacturing requires a high level of reconfigurability and flexibility in production -- especially in production planning and control --, effective information systems, as well as suitable production concepts. Multi-agent systems theoretically provide the required features, but a lack of informational integration and organizational incompatibilities lead to low applicability. Internet based production concepts provide the necessary interoperability and organizational alignment to support an overall application of multi-agent systems in mass customization. The intended decentralization of organizations in Internet based production concepts conform to the modular structure of multi-agent systems. A coordinated application leads to an enabling of mass customization.

The material presented in this paper is focused on the characteristics of open computational systems and, in particular, the issue of coordinating behavior in such systems, i.e. systemic coordination. Firstly, we introduce a conceptual framework for characterizing systemic coordination at different levels abstraction. Secondly, challenges and opportunities of this framework is outlined as a matter of exploiting a Service-oriented layered architecture for communicating entities (SOLACE) in combination with a particular coordination model (TuCSoN). In the context of systems engineering, we consider SOLACE and TuCSoN to be examples of the basic tools required for support of systemic coordination, i.e., the continuous process of construction and observation of open computational systems and their evolving interaction space. Finally, we outline the impact of these tools on empirical aspects of systemic coordination.

partial fulfillment of the requirements for the degree of Master of Science in Software Engineering. The thesis is equivalent to 10 weeks of full time studies. Contact Information: Author(s):

This paper describes the behavior observed in a class of cellular automata that we have defined as "dissipative", i.e., cellular automata for which the external environment can somehow inject "energy " to dynamically influence the evolution of the automata. In this class of cellular automata, we have observed that stable macro-level global structures emerge from local interactions among cells. Since dissipative cellular automata express characteristics strongly resembling those of open distributed systems, we expect that similar sorts of macro-level behaviors are likely to emerge in real world systems of the same nature and need to be studied, controlled, and possibly fruitfully exploited. A preliminary set of experiments reporting two ways of indirectly controlling the behavior of DCA are reported and discussed w.r.t. the possibility of applying similar sort of indirect control on open distributed systems. 1.