Modeling Crosscutting Services with UML Sequence Diagrams

Current software systems increasingly consist of distributed interacting components. The use of web services and similar middleware technologies strongly fosters such architectures. The complexity resulting from a high degree of interaction between distributed components – that we face with web service orchestration for example – poses severe problems. A promising approach to handle this intricacy is service-oriented development; in particular with a do-main-unspecific service notion based on interaction patterns. Here, a

service

is defined by the interplay of distributed system entities, which can be modeled using UML Sequence Diagrams. However, we often face functionality that affects or is spanned across the behavior of other services; a similar concept to aspects in Aspect-Oriented Programming. In the service-oriented world, such aspects form

crosscutting services

. In this paper we show how to model those; we introduce aspect-oriented modeling techniques for UML Sequence Dia-grams and show their usefulness by means of a running example.