1. Modeling a Service and Session Calculus with Hierarchical Graph Transformation Joint work with Roberto Bruni and Andrea Corradini, second part Ugo Montanari Università di Pisa GraMoT, International Colloquium on Graph and Model Transformation on the occasion of the 65th birthday of Hartmut Ehrig February 11 –12, 2010, Technische Universität Berlin

2. 2 Service-Oriented Systems  Selling services is the biggest growth business in the IT industry  Service  autonomous, platform-independent computational entity that can be described, published, categorised, discovered  services can be dynamically assembled for developing massively distributed, interoperable, evolvable systems and applications  Service-Oriented Computing  Common to develop systems using methods from a “static” point-of-view of component architecture  SoC emphasises dynamic communication, semantics and quality assurance  Service-Oriented Computing Challenges  Specifying and querying services  Correctness and consistency  Composition of services requires availability and reliability  Design for verifiable SLAs  Functional and non-functional properties  Evaluating and implementing security, sustained performance, adaptive behaviour, …  Deployment and re-engineering GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

3. 3 2. The SENSORIA Project  IST-FET Integrated Project 2005-2009/10  Coordinator: LMU München  19 Partners: U. Pisa, Florence, Bologna, Trento, Leicester, Edinburgh, Imperial College, University College, Lisbon, Warsaw, Budapest, DTU, ISTI Pisa, FAST, S&N, Telecom Italia, MIP Politecnico di Milano, ATX Technologies SA, Cirquent (replacing FAST since 1.1.2008)  Novel comprehensive approach to engineering of software systems for Service-Oriented Overlay Computers integrating  foundational theories, techniques, and methods and  pragmatic software engineering  Application areas  e-financeautomotive systems  e-learningtelecommunications GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part www.sensoria-ist.eu

4. 4 SENSORIA Development Process (WP7) SENSORIA Development Env. Dissemination, Demonstration, Training, Project Managmnt (WP9-12) SENSORIA WP Structure and Approach Service-oriented Modelling (WP1) Deployment Runtime (WP6) Service-oriented Calculi (WP2+5) Transform (WP7) Qualitative Analysis (WP3) Quantitative Analysis (WP4) Case Studies (WP8) Legacy Code (WP6) GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part www.sensoria-ist.eu

5. 5 Hierarchical Graph Models of Extended Core Calculi  Why graph models?  More natural for distributed systems  Built-in structural axioms  Uniform treatment of most ordinary process algebras (e.g. via the SHR approach)  Why hierarchical?  Nested structures: ambients, block structure, sessions, transactions, etc.  Interaction between siblings, without referring to the closest common ancestor  Yet another graph model?  Bigraphs by Robin Milner (2003)  place graph for localities and link graph for connectivity  Semantics via reduction rules and minimal contexts  Gs-monoidal graphs (gs-graphs) by Ferrari and Montanari (1997)  Based on gs-monoidal categories by Corradini and Gadducci  Sensoria approach based on ADR metamodel  An algebra of hierarchical graphs and its graphical representations  Top view & side view (see presentation by Andrea Corradini)  Applications to Sensoria  Transaction workflows (Sagas)  Service sessions (CaSPiS) GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

6. Key Ingredients of CaSPiS  Service definition  s.P  Service invocation  s.Q  Session  bi-directional, nested  ( r)(r Q | r P) s.P s.Q PQ 6 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

7. (?x)P vQvQ vQvQ Intra-Session Communication I  Abstraction  (?x)P  Concretion   v  Q  Intra-session communication 7 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

8.  Abstraction  (?x)P  Concretion   v  Q  Intra-session communication (?x)P vQvQ P[v/x] Q 8 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part Intra-Session Communication II

9.  CaSPiS allows only for a controlled form of inter-session communication   v   Q vQvQ 9 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part Inter-Session Communication I

10.  CaSPiS allows only a for limited form of inter-session communication   v   Q Q vv 10 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part Inter-Session Communication II

11. Example: Successor I !succ.(?x)  x+1  succ.  5  (?n)  n   11 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

12. Example: Successor II  5  (?n)  n   (?x)  x+1  !succ.(?x)  x+1  12 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

13. Example: Successor III (?n)  n    5+1  !succ.(?x)  x+1  13 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

14. Example: Successor IV (?n)  n   66 !succ.(?x)  x+1  14 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

15. Example: Successor V 66 !succ.(?x)  x+1  15 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

16. Example: Successor VI 66 !succ.(?x)  x+1  16 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

17. Sessions are Permeable to Service Invocation I 17 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

18. Sessions are Permeable to Service Invocation II 18 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

19. Sessions are Permeable to Service Invocation III 19 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

20. Pipeline I (?x)Q P 55  11  77 (?x)Q 20 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

21. Pipeline II  Pipeline  P > Q (?x)Q P 55 77 Q[11/x] 21 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

22. Pipeline  Pipeline  P > Q (?x)Q P Q[11/x] Q[5/x] Q[7/x] 22 GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part

23. Syntax and Stuctural Axioms of CaSPiS GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part 23

24. CaSPiS encoding over the Design Algebra, I GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part 24

25. CaSPiS encoding over the Design Algebra, II GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part 25

26. Transformation Rules for CaSPiS Reduction Semantics, I GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part 26

27. Transformation Rules for CaSPiS Reduction Semantics, II GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part 27

28. Transformation Rules for CaSPiS Reduction Semantics, III GraMoT, February 11 – 12, 2010, TUB, Ugo Montanari, Modeling a Service and Session Calculus with Hierarchical Graph Transformation, 2nd part 28