1. Specification of IT Systems Mandatory Exercise Week 5 Group 3, Søren Vestergaard, Smari Waage, Belma Boyraz, Jannick Hoy

2. OTA - Context diagram Communication between SuD and the external entities that make up the composite system. A user communicates with the system through his browser, which then sends and receives in/output from the SuD, which in turn interfaces with the external web services of the different travel element types to produce the desired system functionality.

3. OTA - Requirements decomposed

4. OTA - Decomposition continued Function based architecture. Main functions include: Reserve, cancel, and search, some of which interface directly with the web service. Partly communication oriented. User communicates with system through one common interface, namely the web site. Communication between web services and system is handled by one component.

5. OTA - Argumentation As a result of the method used in the decomposition, the functional approach, the functions of the diagrams will correspond roughly to the functions defined in the refinement tree. One exception being the “edit” function, which has been shelved because of lacking support in web services.