A Goal-Based Organizational Perspective on Multi-Agent Architectures

1. A Goal-Based Organizational Perspective on Multi-Agent Architectures † Department of Computer Science University of Toronto Toronto M5S 3G4, Canada ‡ Department of Mathematics University of Trento Trento I-38100, Italy Manuel Kolp † Paolo Giorgini ‡ John Mylopoulos † ATAL’01 - August 2 2001, Seattle, USA

2. Motivation • Multi-agent system: organization of individuals to achieve particular, possible common goals. • Using same concepts for requirementsandarchitectures • Multi-Agents architecture as organization and intentional structures • Coordinated autonomous components withgoalsto fulfil and social inter-dependencies ( i*) • Conceptsfromorganizationtheoryandmodeling • Ontology: 3 levels (Macro, micro, atomic) • Part ofTROPOS(http://www.cs.toronto.edu/km/tropos): • Requirements-Driven Development Methodology for Agent-Oriented Software Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

3. i*: an Organizational Modeling Framework Media Shop Goal Resource Task Softgoal Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

4. Multi-Agent Architectures as Social Structures • Global architecture in terms of interconnected social components. • 3 levels • 1Macrolevel : OrganizationalStyles (Organization Theory) • Vertical Integration, Pyramid, Joint Venture, Structure in 5, Bidding, Hierarchical Contracting, Co-optation, Takeover • 2Micro level : Social Patterns (Agent, COOPIS Community) • Broker, Matchmaker, Contract-Net, Mediator, Monitor, Embassy, Wrapper, Master-Slave, ... • 3Atomic : Social and intentional concepts – i* Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

5. Organization Theory • Mintzberg, Scott, Galbraith, … • Studies alternatives andmodelsfor (business) organizations • Used to model thecoordinationof business stakeholders -- individuals, physical or social systems -- to achieve common (business)goals. • Structure in 5, Pyramid, Takeover, Joint Venture, Cooptation, Hierarchical Contracting, Vertical Integration, Bidding, Merger, Equity Agreement, Virtual Organization, … Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

6. Structure in 5 • Strategic and logistic components found in organizations. • Operational core:basic operations -- the input, processing, output associated with running the organization. • Strategicapex: executive,strategic decisions. • Support : Assists the operation core for non-operational services outside the basic flow of operational procedures. • Technostructure : standardizes the behavior of other components, help the system adapt to its environment. • Middle line : Actors who join the apex to the core. Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

7. Structure in 5 in i* and Telos TELL CLASS StructureIn5MetaClass IN Class WITH /*Class is a MetaMetaClass*/ attribute name: String part, exclusivePart, dependentPart ApexMetaClass: Class CoordinationMetaClass: Class MiddleAgencyMetaClass: Class SupportMetaClass: Class OperationalCoreMetaClass: Class END StructureIn5MetaClass In i* In Telos Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

8. Vertical Integration & Joint Venture Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

9. Non Organizational (Classical) Architecture Styles Problems A mobile robot layered architecture Information exchange not always straight-forward Often need to establish direct communication Data and control hierarchies not separated Prevent the dynamic manipulation of components From [Software Architecture: Perspective on an Emerging Discipline, Shaw, Garland, 96] Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

10. Mobile Robot Architecture: Structure-in-5 More distributed architecture Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

11. Software Quality Attributes Predictability, Security, Adaptability, Cooperativity, Competitivity, Availability, Integrity, Modularity, Aggregability Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

12. Example: A User 2 On-line Buying System • Media taxonomy • on-line catalog • DBMS • E-Shopping Cart • Check In • Buying • Check Out • Search Engine • catalog browser • Keywords • full-text • Billing Processor • $ transactions • orders • Multimedia • description • samples Security, Availability, Adaptability, … Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

13. Goal Analysis: Selecting System Architecture Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

14. A Joint-Venture E-commerce Architecture E-business styles: on web, protocols, technologies Not on business processes, NFRs No organization of the architecture, conceptual high-level perspective From Security, Availability, Adaptability Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

15. Social Patterns Monitor Matchmaker Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

16. Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

17. Assigning Agent Roles to Actors Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001

18. Conclusion • Multi-Agents architectures described with concepts from requirements and organization modeling associal and intentional structures • -> Narrows the gap requirements / architecture • Best suited to open, dynamic and distributed applications andorganization information systems • Ontology on 3 levels: • Macro: Organizational Styles, Micro:Social Patterns, Atomic:i* notions • In progress • Formalizing the styles, patterns, Instantiation of a style, pattern ?? • Decision Algorithms, • From Actors to Agents Manuel Kolp, University of Toronto, Department of Computer Science © 2000-2001