Multi-Agent Systems for E-Health and Telemedicine

Background

Although there are several definitions of agent (see, e.g., Russell & Norvig, 2003; Wooldridge & Jennings, 1995; Genesereth & Ketchpel, 1994), all the definitions agree that an agent is essentially an autonomous software entity that should at least be designed to operate continuously in dynamic and uncertain environments, reacting to events while showing an intelligent behavior to pursue its own objectives. An agent usually provides interoperable interfaces for interacting with other agents, either concurrently or cooperatively, exchanging messages formulated according to some syntax, semantics and pragmatics. Since an agent behaves proactively, it requires some degree of trust by its user, and it can receive delegations from either human users or other agents in the form of required actions or desired goals, matched with permissions to access necessary resources. Additionally, an agent may also be able to perform complex reasoning at run-time and can also learn and change their behavior over time, to improve its performance. Finally, it is even able to move for one computational node to another, to follow its own user or to exploit some local resource more efficiently.

Agent-based systems are often realized by loosely coupling various agents, i.e. autonomous software entities, thus modelling a proper multi-agent system, characterized by a higher level of modularity and a richer descriptive model, if compared with a solitary agent working within its environment – either with the presence of users or not. Multi-agent systems can be also considered as abstractions capable of capturing the essence of many software systems at different levels of detail, rather than a single technology supporting the realization of distributed intelligent systems. In particular, agents and multi-agent systems are often considered the highest system level (Newel, 1982; Jennings, 2000) that we can access today and they are meant to provide a truly novel level of abstraction in the analysis, design and implementation of complex software systems (Bergenti & Huhns, 2004).