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Modelling and Validation of Distributed Systems: Research Area and Thesis Opportunities

Jens Bæk Jørgensen

Department of Computer Science

University of Aarhus

jbj@daimi.au.dk

Master’s Thesis Preparation, September 11 2006

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Research areas and research group

Research Areas Modelling (in particular Coloured Petri Nets) Software Engineering Communication Protocols

Research Group Kurt Jensen, Søren Christensen Lars M. Kristensen, Jens Bæk Jørgensen Lisa Wells Michael Westergaard, Kristian Bisgaard Lassen, Simon

Tjell, Mikkel Baun Kjærgård, Doina Bucur, Paul Fleischer Student programmers

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Coloured Petri Nets

Formal modelling language [Jensen, 1980]

Theory- models- basic concepts- analysis methods

Tools- editing- simulation- verification

Practical Use- specification- validation- verification

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Software engineering:Requirements engineering for a new bank system, the Adviser Portal (AP)

Joint project with BankdataScope of AP

15 Danish banks 15 software developers in three years

Main goals Increased efficiency Increased quality

AP must be aligned well with bank work processes

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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 supportedby a new computer system

- Example of work process: blanc loan advise

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Blanc loan advise EUC: informal tier

”The customer comes into the banks and says to his adviser that he wants to take a trip to Paris …”

Main advantage: Easily understandable

Drawback: Not executable

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Blanc loan advise EUC: formal tier

A Coloured Petri Nets (CPN) model

Main advantage: Executable Drawback: Not easily

understandable

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Blanc loan advise EUC: animation tier

Consistent with the formal tier: Shows the CPN model’s states and state transitions, but in another ”language”

Combines the main advantages of the informal tier and the formal tier Executable Understandable

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Examples of thesis topics

Validation of the EUC approach Interplay between informal and formal descriptionsFrom business goals via user requirements to

software requirements From EUCs to implementations: CPNs -> BPEL4WS

(workflow language of IBM WebSphere)

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Software engineering: Estimation of worst-case memory usage of mobile phones software

Joint project with Nokia Research CenterCurrent situation at Nokia

Necessary to estimate worst-case memory usage early Software architecture descriptions include estimates of

expected memory usage of relevant classes, components, and messages

Necessary to consider interaction scenariosProposed solution

Combined use of the Unified Modeling Language (UML) and Coloured Petri Nets (CPN)

Development of tool support

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Memory estimation tool

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Examples of possible thesis topics

Validation of the memory estimation toolExtensions of the tool, e.g., modify to use live

sequence charts as inputConsider other quality attributes of mobile phones

software (or, more generally, embedded systems), e.g., performance

Study possible interplay between CPN Tools and high-end UML tools, e.g. Rhapsody, RealTime Rose

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Communication protocols: Mobile ad hoc networking

Joint project with Ericsson TelebitExplore the use of the Internet Protocol version 6

(IPv6) protocol suite in the context of ad-hoc networking

Application of Coloured Petri Nets (CPN) and supporting computer tools in the development of communication protocols

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Mobile ad-hoc networks

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Hybrid network architecture

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Examples of thesis topics

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Examples of theses

Modelling and analysis of the communication protocol TTCAN Modelling and analysis of routing in mobile ad hoc networks Creating a light-weight requirements engineering process for

Grundfos Modelling and analysis of multicast communication in

windmills for Vestas Routing and TCP performance in mobile ad hoc networks Evaluation of broadcast based protocols for data

dissemination in traffic warning networks The rise and institutionalization of Computer Science at

University of Aarhus ...

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Summary

We will be happy to talk to you about supervising your thesis, if your interests include one or more of these issues Modelling (e.g., CPN, UML) Software engineering (e.g, requirements engineering,

workflow systems, model-driven development) Communication protocols and distributed systems