Interactions and Role Identification (IRI) aims at decomposing a global behavior embodied by an organization into smaller interacting behaviors. Each of these finer grained behaviors will be exhibited by a Role. Interacting roles must be defined in the same organization that provides the interaction context. The goal of each Role is to contribute to the fulfillment of (a part of) the requirements of the organization it belongs to.
This activity also aims at completing the system delimitation started in the
domain requirements description activity. Before trying to develop a system, the
perimeter of the application has to be defined. Role is a parametrized class that can be instantiated in Common Role (often called just Role) or Boundary Role. This latter has been designed to work at the borders of the designed system. Boundary Roles can be, for instance, used to control external sensors/effectors or to interact
with other agent-based and non-agent-based systems. The resulting diagram is a
class diagram where classes represent roles (stereotypes are used to differentiate
common and boundary roles), packages represent organizations and relationships
describes interactions among roles or contributions (to the achievement of a goal)
from one organization to another. Performing this activity is usually an iterative
process coordinated with the following Scenarios Description one. In this latter, the
elements (mainly roles) here depicted from a structural point of view are exploited
in their dynamical behavior.
Contents |
Goal
Role identification aims at decomposing a global behavior embodied by an organization into smaller interacting behaviors. Each of these fine grained behaviors will be represented by a role.
Input
The associations between requirements and organizations, and the relations between concepts inside the domain ontology constitute the inputs for the Role Identification activity.
Output
To describe the static structure of an organization an UML profile for class diagram is used. Each role is represented by a stereotyped class and interactions are represented by associations between roles.
MAS Meta-Model Elements
Define(AbstractRole), Define(Interaction), Relate( Organization, AbstractRole), Relate(Organization, Interaction), Relate( AbstractRole, Interaction).
Work to be done
Role and Interactions are deduced from the set of text descriptions of the system usage scenarios, and from the previously identified organizations. The use of Organizational Design Patterns can also offer a good way to validate the behavioral decomposition by trying to match the current solution to an already well-know one.
Methodological Guidelines
The first step consists in looking into scenarios that can be deduced from use case diagrams to identify interactions. Let us suppose, for instance that organization O1 is assigned to fulfill requirements represented by use cases A and B. Use case B has an ’include’ relationship with use case C assigned to organization O2. This encourages the designer to explore the possibility of a scenario where a role of O2 interacts with another role of O1 in order to provide to O1 the result of a capacity that belongs to O2. Another guideline for roles identification consists in looking at the structure of the ontology in order to find elements that suggest some hierarchical structure that could evoke an holonic configuration with interacting roles (usually such a configuration is also useful for organizations identification as it has been said before).
Suggested notation
The previous UML profile for class diagram introduced to describe ontology, is also used to statically describe organizations. Table 1 details the part of this profile related to organization description and the associated mapping between ASPECS meta-model concepts and UML constructs.
| ASPECS Item | UML Construct | UML Stereotype |
|---|---|---|
| AbstractRole | Class | role |
| BoundaryRole | Class | boundary role |
| AbstractCapacity | Class | capacity |
| Organisation | Package | organisation |
| Interaction | Association | interaction |
| Interaction | Association Class | interaction |
| Requirement | Note | description |
| Non functional Requirement | Note | description |
