Acknowledgment

This paper mostly summarizes the results of a diploma thesis carried out by the first author as part of a joint program between the University of Munich (Munich Network Management MNM Team) and the IBM Zurich Research Laboratory. The Distributed Systems and Network Managment Group at the IBM Zurich Research Laboratory is headed by Dr. Metin Feridun. The MNM Team directed by Prof. Dr. Heinz-Gerd Hegering is a group of researchers of the University of Munich, the Munich University of Technology, and the Leibniz Supercomputing Center of the Bavarian Academy of Sciences. We thank our colleagues at these sites for their encouragement, helpful discussions and comments on previous versions of this paper.