Content

1. Introduction

1.1 Fields of Research and Goals of the Thesis

1.2 Overview

2. Group Communication Systems

2.1 Group Communication Applications

2.2 ITU H.32x

2.3 Group Communication in the Internet

2.4 CORBA

2.5 Summary

3. Scalable Conferencing Control Service

3.1 Service Model

3.2 Protocol Mechanisms

3.3 Implementation Design

3.4 Assessment of SCCCS

3.5 Performance Evaluation of SCCCS

3.6 Summary

4. Group Communication Modeling

4.1 Motivation

4.2 Related Work

4.3 Group Communication Description Language

4.4 Realization with Event-based Simulation

4.5 Realization with Petri Nets

4.6 Summary

5. Resource Management Evaluation

5.1 Classification of the Tree Topology

5.2 Evaluation using Simple Probabilities

5.3 Evaluation using SPNs

5.4 Evaluation with Simulation

5.5 Summary

6. Reconfiguration Evaluation

6.1 Scenario 1 – Panel Discussion

6.2 Scenario 2 – Separated Sessions

6.3 Scenario 3 – Worst Case Scenario

6.4 Compuational Effort

6.5 Setting Guidelines for the Reconfiguration

6.6 Summary

7. Conclusions and Future Work

Appendix A SDL Template for GCDL

Appendix B Abbreviations

Appendix C List of Figures and Tables

Appendix D References

Appendix E Curriculum Vitae