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Logo: SRA/Leibniz Universität Hannover
Logo Leibniz Universität Hannover
Logo: SRA/Leibniz Universität Hannover
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Leitung:Prof. Dr.-Ing. Müller-Schloer Christian
Laufzeit:11.2009 -
Bild OC-Trust


  • Prof. Dr.-Ing. Müller-Schloer (Systems Engineering, Hannover), 
  • Prof. Dr. Jörg Hähner (Organic Computing, Augsburg)
  • Prof. Dr. André (Multimedia Concepts and Applications, Augsburg), 
  • Prof. Dr. Reif (Software Engineering, Augsburg), 
  • Prof. Dr. Ungerer (Systems and Networking, Augsburg)

Systems designed according to the Organic Computing paradigm, can quickly adapt their behaviour and even their architecture to changing situations. This reorganisation can be triggered by environmental conditions or other constraints that have influence on these systems. The adaption of such a system can improve the system, as it can become more applicable for the environment it is used in or more robust to certain failures. However, as the adaption can change the system fundamentally, a new approach is needed to cover for the possible loss of trustworthiness of the system. In the project OC-Trust, we at SRA focus on system-to-system Trust. We are especially interested in Trust relations between entites of the system, expressed as credibility of these entities.

The following is a short summary of the work we conducted in cooperation with our project partners:

Throughout the project we address basic technologies, integration, application and extension of Trust mechanisms in each of the following fields:

  • Agent level
  • System level
  • Institutional control
  • Demonstration and evaluation

Agent level

Here, our focus is on the design of trust-adaptive agents. In this context, we have defined and implemented an agent architecture that allows agents to make strategic short- and long-term decisions based on the notion of Trust. This is backed up by the utilisation of the Observer/Controller-paradigm known from several Organic Computing projects. Here, the Observer is responsible for generating a meaningful and correct situation description for the agent. As we are mainly interested in Trust, this description integrates dimensions as agent reputation and personal experiences with other agents. The Controller is responsible for the generation of adequate behavioural strategies for the observed situations. This incorporates such diverse behaviours as selfish improvement of the agent's fitness or altruistic efforts to improve the overall system (with possible negative side-effects on the fitness of the agent).

In related future work, amongst others, we plan to address the development of a fine-grained situation description and the application of machine learning techniques to dynamically map situations descriptions to effective strategies.

System level:

On the system level we examine the decentralised formation of Trust-based agent organisations that increase the member's effectiveness. These so-called Trusted Communities (TC) come in two flavours: The implicite TC is built between agents with mutual Trust relations without the explicite knowledge of the agents. Membership is therefore defined by the system designer and the TC concept is used mainly analytically. On the other hand, the explicite TC is formed based on membership contraints and managed explicitely by an according agent. Members here, are known to other members and can be treated different than non-members, allowing for elaborate strategic options and further effectiveness improvement.

In related future work, amongst others, we plan to investigate and implement the concept of explicite Trusted Communities and examine their lifecycle management and evaluate their potential for fitness improvement. 


Institutional control:

Institutional control can guide agents through norms and sanctioning mechanisms to avoid the emergence of negative behaviour. In the regarded systems selfish strategies and other local behaviour can lead to ineffective global performance of the system. Institutions can observe local behaviour and impose norms whenever the system is likely to take damage from this behaviour. In future work we want to examine how institutional control via deontic norms can improve the system while maintaing a high degree of subsystem autonomy. 


Demonstration and evaluation:

In order to evaluate the applicability of the developed techniques and mechanisms to Organic Systems, we apply them to a demonstration scenario. This demonstrator is set in the area of Desktop Grid Computing. Here, we built a system that incoporates trust-adaptive agents as control entities of a Desktop Grid Client software. The agents act on behalf of a user and apply the described mechanisms to efficiently process jobs created by user applications. 

Currently, we work with a simulation of this system - it is planned to shift to an actual Desktop Grid System based on a middleware developed by our project partners.

Available student theses

Theses can be written in German or English. If you are interested in a topic or have own ideas about a thesis, please do not hesitate to contact us.

Supervised student theses

  1. [Blu10] Bluhm, D.: "Analysis and implementation of social cooperation strategies based on an evolutionary trust model". Bachelor Thesis, 2010.
  2. [Tav10] Tavakkoli, H.: "Bachelor Thesis: Untersuchung von Metriken zum Vergleich spieltheoretischer Ansätze in Multiagentensystemen". Bachelor Thesis, 2010.
  3. [Bae10] Bähre, P.: "Entwurf und Implementierung einer Desktop Grid Applikation zur Gesichtserkennung". Master Thesis, 2010.
  4. [Bec10] Becher, R.: "Analysis of the applicability of Game-theoretic approaches to trust-based self-organising systems". Bachelor Thesis, 2010.
  5. [Bro11] Brockmann, F.: "Analyse und Vergleich von Trust- und Reputationsmetriken für ein Desktop Grid System". Master Thesis, 2011.
  6. [Thi11] Thimm, Markus: "Spieltheoretische Analyse des Einflusses vergangener Entscheidungen auf die Strategiewahl". Bachelor Thesis, 2011.
  7. [Bus11] Busch, S.: "Untersuchung des Systemverhaltens eines vertrauensbasierten Desktop Grid Systems", Bachelor thesis, 2011
  8. [S-P11] Saint-Paul, F.: "Erweiterung und Evaluation einer Desktop Grid Simulation für vertrauenswürdige Agenten - Volatilität und Lokalität", Master thesis, 2011
  9. [Jas11] Jaschke, S.: "Implementierung und Evaluation von auktionsbasierten Agenten für ein Desktop Grid System", Master thesis, 2011
  10. [Sei12] Seifert, C.: "Analyse und Vergleich von adaptiven und trustbasierten Desktop Grid Matchmaking-Verfahren", Master thesis, 2012
  11. [Sch12] Schreiber, N.: "Analyse und Implementierung eines Lernverfahrens für ein Desktop Grid System", Master thesis, 2012
  12. [Wal12] Wall, A.:  "Entwicklung von vertrauensbasierten Mechanismen zur Steigerung der Robustheit von ošffenen Systemen", Master thesis, 2012
  13. [Beh13] Behrens, D.: "Komposition einer Trusted Community: Metriken, Strategien und Szenarien", Bachelor thesis, in process
  14. [Thi13] Thimm, M.: "Berücksichtigung institutionell vorgegebener Normen in trust-strategischen Agenten", Master thesis, in process


Related Workshops

Trustworthy Self-Organizing Systems (TSOS): Workshop at the Tenth Annual Conference on Privacy, Security and Trust, Paris, July 16-18, 2012 

Trustworthy Self-Organizing Systems (TSOS): Workshop at the Fourth IEEE International Conference on Self-Adaptive and Self-Organizing Systems 2010

TSOS 2010, Budapest, September 27 – October 1, 2010

Trustworthy Self-Organizing Systems (TSOS): Workshop at the Fifth IEEE International Conference on Self-Adaptive and Self-Organizing Systems 2011

TSOS 2011, Ann Arbor, October 3, 2011

Link: swt.informatik.uni-augsburg.de/tsos/

Further information and contact


  • M.Sc. Yvonne Bernard
  • M.Sc. Lukas Klejnowski


Yvonne Bernard, Lukas Klejnowski, Jörg Hähner, Christian Müller-Schloer (2010): Towards Trust in Desktop Grid Systems, ccgrid, pp.637-642, 2010 10th IEEE/ACM International Conference on Cluster, Cloud and Grid Computing

Jan-Philipp Steghöfer, Rolf Kiefhaber, Karin Leichtenstern, Yvonne Bernard, Lukas Klejnowski, Wolfgang Reif, Theo Ungerer, Elisabeth André, Jörg Hähner, and Christian Müller-Schloer (2010): Trustworthy Organic Computing Systems: Challenges and Perspectives, Proceedings of the 7th International Conference on Autonomic and Trusted Computing (ATC 2010), Springer

Jan-Philipp Steghöfer, Florian Nafz, Wolfgang Reif, Yvonne Bernard, Lukas Klejnowski, Jörg Hähner and Christian Müller-Schloer (2010): Formal Specification and Analysis of Trusted Communities, Proceedings of the 2010 Fourth IEEE International Conference on Self-Adaptive and Self-Organizing Systems Workshop (SASOW 2010)

Lukas Klejnowski, Yvonne Bernard, Jörg Hähner and Christian Müller-Schloer (2010): An architecture for trust-adaptive agents, Proceedings of the 2010 Fourth IEEE International Conference on Self-Adaptive and Self-Organizing Systems Workshop (SASOW 2010)

Yvonne Bernard, Lukas Klejnowski, Emre Cakar, Jörg Hähner and Christian Müller-Schloer (2011): Efficiency and robustness using Trusted Communities in a Trusted Desktop Grid, Proceedings of the 2011 Fifth IEEE International Conference on Self-Adaptive and Self-Organizing Systems Workshop (SASOW 2011)

Yvonne Bernard, Lukas Klejnowski, Ronald Becher, Markus Thimm, Jörg Hähner, Christian Müller-Schloer (2011): Grid agent cooperation strategies inspired by Game Theory, 4. Workshop Grid-Technologie für den Entwurf technischer Systeme, Dresden, 21.-22. September 2011, ISSN 1862-622X

Gerrit Anders, Lukas Klejnowski, Jan-Philipp Steghöfer, Florian Siefert, Wolfgang Reif (2011): Reference Architectures for Trustworthy Energy Management and Desktop Grid Computing Applications, Technical Report 2011-11, Universitätsbibliothek der Universität Augsburg, Universitätsstr. 22, 86159 Augsburg, 2011

Yvonne Bernard, Lukas Klejnowski, David Bluhm, Jörg Hähner and Christian Müller-Schloer (2012): An Evolutionary Approach to Grid Computing Agents, Proc. of the Italian Workshop on Artificial Life and Evolutionary Computation, 2012 , pp. 1-12. Best Paper Award related to self-aware autonomic systems

Lukas Klejnowski, Yvonne Bernard, Christian Müller-Schloer and Jörg Hähner (2012): Using Trust to reduce wasteful computation in open Desktop Grid Systems, at TSOS 2012 at 10th Annual Conference on Privacy, Security and Trust

Yvonne Bernard, Lukas Klejnowski, David Bluhm, Jörg Hähner, Christian Müller-Schloer (2012): Self-organisation and Evolution for Trust-adaptive Grid Computing Agents, in "Evolution, Complexity and Artificial Life", Springer

Yvonne Bernard, Lukas Klejnowski, Christian Müller-Schloer, Jeremy Pitt, Julia Schaumeier (2012): Enduring Institutions and Self-Organising Trust-Adaptive Systems for an Open Grid Computing Infrastructure, SASO Workshops, 2012, 163-168, Sixth IEEE International Conference on Self-Adaptive and Self-Organizing Systems Workshops, SASOW 2012, Lyon, France, September 10-14, 201, IEEE Computer Society

Lukas Klejnowski, Yvonne Bernard, Gerrit Anders, Christian Müller-Schloer, Wolfgang Reif (2013): Trusted Community - A Trust-Based Multi-Agent Organisation for Open Systems, ICAART 2013 - Proceedings of the 5th International Conference on Agents and Artificial Intelligence, Barcelona, Spain, 15-18 February, 2013

Lukas Klejnowski, Sebastian Niemann, Yvonne Bernard and Christian Müller-Schloer (2013): Using Trusted Communities to improve the speedup of agents in a Desktop Grid System, Proceedings of the 7th International Symposium on Intelligent Distributed Computing - IDC'2013, Prague, Czech Republic, 2013

Gerrit Anders, Jan-Philipp Steghöfer, Lukas Klejnowski, Michael Wissner, Stephan Hammer, Florian Siefert, Hella Seebach, Yyonne Bernard, Wolfgang Reif, Elisabeth André, and Christian Müller-Schloer (2013): Reference Architectures for Trustworthy Energy Management, Desktop Grid Computing Applications, and Ubiqitous Display Environments, Technical Report 2013-05, Universitätsbibliothek der Universität Augsburg, Universitätsstr. 22, 86159 Augsburg, 2013

Mathias Pacher, Christian Müller-Schloer, Yvonne Bernard, Lukas Klejnowski (2013): Social Awareness in Technical Systems "The Computer After Me"', Imperial College Press / World Scientific Book, accepted for publication 2013