1 Modelling and Validation of Distributed Systems: Research Area and Thesis Opportunities Jens Bæk Jørgensen Department of Computer Science University of Aarhus Master’s Thesis Preparation, September

2 Research areas and research group zResearch Areas yModelling (in particular Coloured Petri Nets) ySoftware Engineering yCommunication Protocols zResearch Group yKurt Jensen, Søren Christensen yLars M. Kristensen, Jens Bæk Jørgensen yLisa Wells yMichael Westergaard, Kristian Bisgaard Lassen, Simon Tjell, Mikkel Baun Kjærgård, Doina Bucur, Paul Fleischer yStudent programmers

3 Coloured Petri Nets zFormal modelling language [Jensen, 1980] Theory - models - basic concepts - analysis methods Tools - editing - simulation - verification Practical Use - specification - validation - verification

4 Software engineering: Requirements engineering for a new bank system, the Adviser Portal (AP) zJoint project with Bankdata zScope of AP y15 Danish banks y15 software developers in three years zMain goals yIncreased efficiency yIncreased quality zAP must be aligned well with bank work processes

5 Alignment approach: Executable Use Cases (EUCs) - Resembles usual prototyping - Used for specification, validation, and elicitation of requirements An EUC describes a work process that must be supported by a new computer system - Example of work process: blanc loan advise

6 Blanc loan advise EUC: informal tier z”The customer comes into the banks and says to his adviser that he wants to take a trip to Paris …” zMain advantage: Easily understandable zDrawback: Not executable

7 Blanc loan advise EUC: formal tier zA Coloured Petri Nets (CPN) model zMain advantage: Executable zDrawback: Not easily understandable

8 Blanc loan advise EUC: animation tier zConsistent with the formal tier: Shows the CPN model’s states and state transitions, but in another ”language” zCombines the main advantages of the informal tier and the formal tier yExecutable yUnderstandable

9 Examples of thesis topics zValidation of the EUC approach zInterplay between informal and formal descriptions zFrom business goals via user requirements to software requirements zFrom EUCs to implementations: CPNs -> BPEL4WS (workflow language of IBM WebSphere)

10 Software engineering: Estimation of worst-case memory usage of mobile phones software zJoint project with Nokia Research Center zCurrent situation at Nokia yNecessary to estimate worst-case memory usage early ySoftware architecture descriptions include estimates of expected memory usage of relevant classes, components, and messages yNecessary to consider interaction scenarios zProposed solution yCombined use of the Unified Modeling Language (UML) and Coloured Petri Nets (CPN) yDevelopment of tool support

11 Memory estimation tool

12 Examples of possible thesis topics zValidation of the memory estimation tool zExtensions of the tool, e.g., modify to use live sequence charts as input zConsider other quality attributes of mobile phones software (or, more generally, embedded systems), e.g., performance zStudy possible interplay between CPN Tools and high-end UML tools, e.g. Rhapsody, RealTime Rose

13 Communication protocols: Mobile ad hoc networking zJoint project with Ericsson Telebit zExplore the use of the Internet Protocol version 6 (IPv6) protocol suite in the context of ad-hoc networking zApplication of Coloured Petri Nets (CPN) and supporting computer tools in the development of communication protocols

14 Mobile ad-hoc networks

15 Hybrid network architecture

16 Examples of thesis topics

17 Examples of theses zModelling and analysis of the communication protocol TTCAN zModelling and analysis of routing in mobile ad hoc networks zCreating a light-weight requirements engineering process for Grundfos zModelling and analysis of multicast communication in windmills for Vestas zRouting and TCP performance in mobile ad hoc networks zEvaluation of broadcast based protocols for data dissemination in traffic warning networks zThe rise and institutionalization of Computer Science at University of Aarhus...

18 Summary zWe will be happy to talk to you about supervising your thesis, if your interests include one or more of these issues yModelling (e.g., CPN, UML) ySoftware engineering (e.g, requirements engineering, workflow systems, model-driven development) yCommunication protocols and distributed systems