Agent Roles and Role Models: New Abstractions for Intelligent Agent System Analysis and Design 2.0 Roles and Role Modelling in Object Oriented Software Engineering 2.1 Overview

This paper presents roles and role models as new abstractions for specifying, modelling, and designing intelligent agent systems. The approach is particularly valuable for applications that involve information and process management because it represents a unified approach. Software agents, objects, processes, organizations, and people can play roles and can therefore be incorporated into a role model. This paper provides an overview of role modelling and describes research at BT that is documenting role model patterns of intelligent agent systems. 1. INTRODUCTION The analysis and design of systems that include intelligent agents, as one type of software engineering, should answer the following questions (along with others): 1. What does this application do ? 2. Should intelligent agents be used in this application ? 3. What does each intelligent agent do ? 4. What goals, responsibilities, tasks, and expertise does each agent have ? 5. How do the intelligent agents interact with each other and with other entities ? 6. What kind of agents and what kind of agent architecture should be used ? Capturing and structuring goals [13] is an approach to analysis that results in a goal model (a goal hierarchy diagram) as an answer to question 1 above. Questions 2 through 6 above involve partitioning the goal model, allocating goals and activities to intelligent agents, objects and people. This is similar to responsibility based design [26] The relatively new area of role modelling [1, 16, 19, 22], as defined in object oriented software engineering, is presented in this paper as a promising approach to addressing questions 3 through 6 above. As described in this paper, role modelling is appropriate for intelligent agent systems because of the following: • Role models emphasize social or interactive behavior. • Roles in a role model work together to accomplish a goal. • Role models are patterns that should be documented and shared. • Roles and role models provide a new abstraction that can unify diverse aspects of a system. Software agents, objects, processes, organizations, and people can play roles, and this is especially important in applications that encompass all these types of entities, such as information and process management. • Role model synergy integrates roles and may be valuable for agent design. • Role model dynamics can be employed to model mobility, adaptive behavior, context switching, and other aspects of agent systems. Roles and role models [1, 16, 19] are relatively new abstractions …