Moving Network Flows without Congestion: Different Models, Different Complexities Wednesday June 1, 2016, 11am Computer Science 302 While the optimal utilization of networks with (multi-commodity) flows is a well-studied research area, the consistent migration of flows is still a relatively young field: If the demands in a network change, how can we satisfy these new demands without losing packets or rate-limiting flows in the process? Central control, as offered by Software Defined Networking, cannot change the network behavior instantaneously. E.g., due to asynchrony, links can be over-utilized in the migration, leading to (temporary) congestion. In this talk, we are going to look at consistent flow migration for different models, ranging from single-destination flows with weak consistency requirements and arbitrary flow paths, to multi-commodity flows along fixed new paths with truly lossless migration. (Joint ongoing work with Sebastian Brandt, Laurent Vanbever, and Roger Wattenhofer) Klaus-Tycho Foerster is a PhD candidate in the Computer Engineering and Networks Laboratory at ETH Zurich, advised by Roger Wattenhofer. Prior to joining ETH as a research assistant, he earned his master degrees in mathematics and computer science, both at the Braunschweig University of Technology. Klaus' research focus lies in distributed computing, graph algorithms, and Software Defined Networking: Funded by Microsoft Research, he is studying the complexity of consistent updates in SDNs.