Remigijus GUSTAS Department of Information Systems, Karlstad University

1. Overlaying Conceptualizations for Managing Complexity of Scenario Specifications Remigijus GUSTAS Department of Information Systems, Karlstad University

2. The way systems are built today remains very primitive Managing complexity (the problem of separation of crosscutting concerns), Blending software and enterprise engineering, architecture across organizational and technical boundaries (alignment problem), Integration of business processes and business data (integrity problem) Continuous innovation (evolution problem). Remigijus Gustas, Remigijus.Gustas@kau.se

3. Separation of Crosscutting Concerns Tangling occurs when component or class, instead of fulfilling a particular concern, encapsulates a diverse set of concerns, Scattering occurs when a particular concern is spread across multiple components, When requirements caused by one concern are modified, designer must to find out how all components are affected by introduced changes, If concerns cannot be separated, the complexity of a system analysis and design task increases exponentially. Remigijus Gustas, Remigijus.Gustas@kau.se

4. Basic Interaction Loop Remigijus Gustas, Remigijus.Gustas@kau.se

5. Service Interaction Loop Value flows (Gordijn et al., 2000) Remigijus Gustas, Remigijus.Gustas@kau.se

6. Conversation for Action Schema Winograd, T., Flores, R Understanding Computers and Cognition: A New Foundation for Design, Ablex Norwood, N.J. (1986) Remigijus Gustas, Remigijus.Gustas@kau.se

7. Structural and Behavioral Aspects of Conceptualizations Remigijus Gustas, Remigijus.Gustas@kau.se

8. Remigijus Gustas, Remigijus.Gustas@kau.se

9. Remigijus Gustas, Remigijus.Gustas@kau.se

10. Jacobson, I., NG, P-W. (2005). Aspect-Oriented Software Development with Use Cases, Pearson Education: Pennsylvania • The Customer requests room by entering the specific room requirements (including the desired period of stay), • The Hotel Reservation System offers various available rooms with different price alternatives, • The Customer may Check Room Details, • The Customer selects the available room (more than one room can be selected), • The Hotel Reservation System creates reservation with the details of all selected hotel rooms and displays information about the required reservation to the Customer. step 3) Check Room Details is represented by an optional use case with the extension point in Reserve Room use case: 3.1) The Customer requests room details, 3.2) The Hotel Reservation System presents room information.

11. Remigijus Gustas, Remigijus.Gustas@kau.se

12. Alternative Actions and Loops Remigijus Gustas, Remigijus.Gustas@kau.se

13. The Standard Transaction Pattern Remigijus Gustas, Remigijus.Gustas@kau.se

14. Remigijus Gustas, Remigijus.Gustas@kau.se

15. The Universal Transaction Pattern Remigijus Gustas, Remigijus.Gustas@kau.se

16. Conclusions • Separation of crosscutting constraints in terms of simple interaction loops is important for system architects to construct scenarios, which have understandable structure. • The presented method helps to integrate interactive, behavioral and structural aspects of conceptualizations across organizational and technical system boundaries. • Advantage of the modeling approach is stability and flexibility of diagrams in dealing with evolutionary changes of requirements and managing complexity. • The method is able to model sequential, iterative, parallel and alternative behavior by introducing underlying and overlaying interaction loops. Remigijus Gustas, Remigijus.Gustas@kau.se