1. Integrating and Orchestrating Services upon a MAS Coordination Infrastructure
Enrico Denti, Alessandro Ricci, Rossella Rubino
DEIS, Università degli Studi di Bologna (Italy)
Sede di Cesena / Bologna

2. Context & Goals Context Goals
Engineering Systems a MAS Coordination Infrastructure (TuCSoN)
Smart Environments
WfMS & CSCW
Goals
Reuse/Integration of (Legacy) Services
, FTP, HTTP, Web Services
Infrastructure support for Service Coordination
Coordination Services
Organisation Services
Context
- Engineering CSCW and WfMS upon MAS Coordination Infrastructure
- Reuse/Integration of Legacy Services ( , FTP, etc..) -
Objective
2 Basic Questions:
1) Come usare un servizio se sono un agente TuCSoN?
More Generally:
Come inquadrare, modellare e utilizzare un servizio su una MAS Coordination/Organisation Infrastructure?
Come sfruttare il supporto infrastrutturale di organizzazione / coordinazione a tal riguardo?
2) Come posso sfruttare l'infrastruttura di coordinazione per affrontare aspetti di composizione e coordinazione dei servizi?

3. Service Oriented Architecture Issues
Service Oriented Issues
Architecture
Registration, Discovery, Access (ex: Web Services, OSGi, Jini...)
Interoperability
Ontologies, Protocols (ex: Semantic Web Effort...)
Composition and Coordination
Choreography & Orchestration (ex: BPEL4WS, WSCI, BPML...)
Our Focus
Enabling Access to Standard/Legacy Services for TuCSoN heterogeneous Agents
heterogeneous computational models & languages
Exploiting coordination and organisation infrastructure facilities to aggregate and orchestrate services
Quali sono le main issues a cui ci si trova di fronte quando si parla di integrazione di servizi
- architettura in generale
- interoperabilità
- composizione e coordinazione
NOI ci siamo focalizzati sul 3 punto

4. Engineering Services IMPACT of Infrastructure model and abstractions
Organisation Model
Structures and Rules
Interaction/Coordination Model
Direct vs. Mediated
Specifying/Enacting/Ruling social activities
Objective vs. Subjective Approaches
And the consequent
Security Model
...
Il modello e le astrazioni fornite/supportate dall’infrastruttura condizionano pesantemente
l’ingegneria dei servizi
In particolare il modello organizzazionale supportato dall’infrastruttura, quello di interazione, di coordinazione, etc...

5. Approaches: Direct (P2P) Models
Marginal Infrastructure Support

6. Approaches: Agent-Mediated Model
Middle-Agents as Mediator

7. Approaches: Tuple-Space-like Model
Mediate Interaction through Shared Information Space
Infrastructure Support
Ex: PageSpace

8. Our approach: Coordination Artifacts
Runtime Customisable Coordination Services
Encapsulating Coordination Policy & Control
Programmed for supporting/automating specific coordination tasks
Infrastructure Abstractions
Predictable, Inspectable, Malleable, Linkable
Role in SOA
Interfaces for Users
Ontology Mediators
Governing Users/Providers concurrency/multiplicity

9. TuCSoN Infrastructure for Coordination Artifacts
Tuple Centres as Coordination Artifacts
Programmable Logic Tuple Spaces
Coordination behaviour programmed in ReSpecT
Agent Coordination Contexts to access Tuple Centres
Runtime Organisation Abstraction
Negotiated by agents to enter the Organisation
Models agent’s active role(s) inside the Organisation
Runtime Interface to access Organisation Resources
Role-Based Access Control

10. Systems on TuCSoN

11. ACC Negotiation & Entrance

12. A Simple Service Model Mapping Service Ontology as Logic Tuples
User Profile
Service Request
Service Result
Coordination Artifact Usage Protocol
Getting Request ID
Inserting Request Info
Reading Request Result

13. An example: Email User Profile Mail Description Service Operations
user_profile(’mail/pop’,Name,info(host(H),user(U),pwd(P)),...)
user_profile(’mail/smtp’,Name,info(host(H),user(U),pwd(P)),... )
Mail Description
mail_header(ID, MsgID, sender(S), recipient(R), subject(X),...)
mail_body(ID, MsgID, ‘content-type’(MIMEType),content(C))
Service Operations
service_request(mail,ProfileName,ID,check_mail(TargetTC))
service_request(mail,ProfileName,ID,send_mail(TargetTC))

14. Sending an ...
reaction(in(sevice_request_id(ID)),(
...
)).

15. Sending an ...

16. Sending an ...

17. Sending an ...

18. Sending an ...

19. Sending an ...

20. Sending an ...

21. Composing and Coordinating Services
Coordination Artifacts as natural services glue
Encapsulating the logic of Service Composition & Coordinations
Two Basic Architectures
Single Tuple Centre
Multiple Tuple Centres

22. A simple scenario: SMS/email coordination

23. A Taste of Service Coordination (1)
Composing Basic and SMS Service
Basic Gluing Activity: “Automatic SMS Sending”
Single Tuple Centre Architecture

24. Single Tuple Centre Approach (1)

25. Single Tuple Centre Approach (2)

26. A Taste of Service Coordination (2)
Multiple Tuple Centres Architecture
Introducing a new coordination artifact for service orchestration

27. Multiple Tuple Centres Approach (1)

28. Multiple Tuple Centres Approach (2)

29. Towards Full-fledged Service Orchestration
Coordination Artifacts used as general purpose Workflow/Orchestration Engines
agents responsible of individual job/task execution
tuple centres encapsulate/enact task coordination
social tasks

30. Outcomes Separation of Concerns Encapsulation of Coordination Policies
agents
coordination artifacts
Encapsulation of Coordination Policies
prescriptiveness & control
runtime adaptability
dynamic inspection/change of coordination artifacts’ coordination behaviour
reuse

31. Ongoing & Future Work Service Catalogue
Current: , ftp, web browsing, LEGO Mindstorms
Ongoing: SMS, Vocal, generic web services
Exploiting the TuCSoN Organisation Support
Service Organisation
Role-based Access Control
Testing/Using Services in System Engineering
Web Service Orchestration & Choreography
BPEL4WS, BPML, WSCI