Dr.sc. Dipl.-Math. Dipl.-Inform.

Klaus-Tycho Foerster

Research Group Communication Technologies
Faculty of Computer Science
University of Vienna
Office 5.47
Währinger Strasse 29
AT - 1090 Vienna
Austria
email: klaus-tycho.foerster@univie.ac.at
Google Scholar: profile
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 Klaus-Tycho Foerster

Short CV: As of 2018, Klaus-Tycho Foerster is a postdoctoral researcher at the University of Vienna, Austria, working with Stefan Schmid. In 2017 he was a postdoc at Aalborg University, Denmark. He was a visiting researcher at Microsoft Research, Redmond, USA, working with Ratul Mahajan for Fall 2016. He received his PhD degree from ETH Zurich in September 2016, supervised by Roger Wattenhofer in the Distributed Computing Group, supported by Microsoft Research. (↗ Extended CV)

Research interests: My research focus revolves around algorithms and complexity in the areas of networking, distributed computing, and didactics, e.g.:

News

Publications

Journals (peer-reviewed, international)

  1. Survey of Consistent Software-Defined Network Updates
    Klaus-Tycho Foerster, Stefan Schmid, and Stefano Vissicchio.
    IEEE Communications Surveys and Tutorials (COMST), to appear.
    Documents: paper pdf link external

  2. On the Complexity of Non-Segregated Routing in Reconfigurable Data Center Architectures
    Klaus-Tycho Foerster, Maciej Pacut, and Stefan Schmid.
    ACM SIGCOMM Computer Communication Review (CCR), April 2019.
    paper pdf

  3. Congestion-Free Rerouting of Multiple Flows in Timed SDNs
    Jiaqi Zheng, Bo Li, Chen Tian, Klaus-Tycho Foerster, Stefan Schmid, Guihai Chen, Jie Wu, and Rui Li .
    IEEE Journal on Selected Areas in Communications (JSAC), Volume 37, Issue 5, pp. 968-981, May 2019.
    Documents: paper pdf link external

  4. Wireless Evacuation on m Rays with k Searchers
    Sebastian Brandt, Klaus-Tycho Foerster, Benjamin Richner, and Roger Wattenhofer.
    Theoretical Computer Science (TCS), to appear
    Documents: paper pdf link external

  5. Loop-Free Route Updates for Software-Defined Networks
    Klaus-Tycho Foerster, Arne Ludwig, Jan Marcinkowski, and Stefan Schmid.
    IEEE/ACM Transactions on Networking (ToN), Volume 26, Issue 1, pp. 328-341, February 2018.
    Documents: paper pdf link external

  6. Local Fast Failover Routing With Low Stretch
    Klaus-Tycho Foerster, Yvonne-Anne Pignolet, Stefan Schmid, and Gilles Tredan.
    ACM SIGCOMM Computer Communication Review (CCR), Volume 48, Issue 1, pp. 35-41, January 2018.
    Documents: paper pdf link external

  7. Charting the Algorithmic Complexity of Waypoint Routing
    Saeed Akhoondian Amiri, Klaus-Tycho Foerster, Riko Jacob, and Stefan Schmid.
    ACM SIGCOMM Computer Communication Review (CCR), Volume 48, Issue 1, pp. 42-48, January 2018.
    Documents: paper pdf link external

  8. Local Checkability, No Strings Attached: (A)cyclicity, Reachability, Loop Free Updates in SDNs
    Klaus-Tycho Foerster, Thomas Luedi, Jochen Seidel, and Roger Wattenhofer.
    Theoretical Computer Science (TCS), Volume 709, pp. 48-63, January 2018.
    Documents: paper pdf link external

  9. Augmenting Flows for the Consistent Migration of Multi-Commodity Single-Destination Flows in SDNs
    Sebastian Brandt, Klaus-Tycho Foerster, and Roger Wattenhofer.
    Pervasive and Mobile Computing (PMC), Volume 36, pp. 134-150, April 2017.
    Documents: paper pdf link external

  10. Lower and Upper Competitive Bounds for Online Directed Graph Exploration
    Klaus-Tycho Foerster and Roger Wattenhofer.
    Theoretical Computer Science (TCS), Volume 655, Part A, pp. 15-29, December 2016.
    Documents: paper pdf link external

Conference and Workshop Proceedings (peer-reviewed, international)

  1. DaRTree: Deadline-aware Multicast Transfers in Reconfigurable Wide-Area Networks
    Long Luo, Klaus-Tycho Foerster, Stefan Schmid, and Hongfang Yu.
    27th IEEE/ACM International Symposium on Quality of Service (IWQoS), Phoenix, AZ, USA, June 2019.
    Documents: paper pdf

  2. Bonsai: Efficient Fast Failover Routing
    Klaus-Tycho Foerster, Andrzej Kamisiński, Yvonne-Anne Pignolet, Stefan Schmid, and Gilles Tredan.
    49th IEEE/IFIP International Conference on Dependable Systems and Networks (DSN), Portland, OR, USA, June 2019.
    Documents: paper pdf

  3. Latency and Consistent Flow Migration: Relax for Lossless Updates
    Klaus-Tycho Foerster, Laurent Vanbever, and Roger Wattenhofer.
    18th IFIP Networking Conference (IFIP Networking), Warsaw, Poland, May 2019.
    Documents: paper pdf

  4. Efficient Non-Segregated Routing for Reconfigurable Demand-Aware Networks
    Thomas Fenz, Klaus-Tycho Foerster, Stefan Schmid, and Anaïs Villedieu.
    18th IFIP Networking Conference (IFIP Networking), Warsaw, Poland, May 2019.
    Documents: paper pdf

  5. On the Power of Preprocessing in Decentralized Network Optimization
    Klaus-Tycho Foerster, Juho Hirvonen, Stefan Schmid, and Jukka Suomela.
    39th IEEE International Conference on Computer Communications (INFOCOM), Paris, France, April 2019.
    Documents: paper pdf

  6. CASA: Congestion and Stretch Aware Static Fast Rerouting
    Klaus-Tycho Foerster, Yvonne-Anne Pignolet, Stefan Schmid, and Gilles Tredan.
    39th IEEE International Conference on Computer Communications (INFOCOM), Paris, France, April 2019.
    Documents: paper pdf

  7. Local Fast Segment Rerouting on Hypercubes
    Klaus-Tycho Foerster, Mahmoud Parham, Stefan Schmid, and Tao Wen.
    22nd International Conference on Principles of Distributed Systems (OPODIS), Hong Kong, December 2018.
    Documents: paper pdf link external

  8. On the Consistent Migration of Splittable Flows: Latency-Awareness and Complexities
    Klaus-Tycho Foerster.
    17th IEEE International Symposium on Network Computing and Applications (NCA), Cambridge, MA, USA, November 2018.
    Documents: paper pdf link external

  9. RADWAN: Rate Adaptive Wide Area Network
    Rachee Singh, Manya Ghobadi, Klaus-Tycho Foerster, Mark Filer, and Phillipa Gill.
    Annual Conference of the ACM Special Interest Group on Data Communication (SIGCOMM), Budapest, Hungary, August 2018.
    Documents: paper pdf link external YouTube

  10. Characterizing the Algorithmic Complexity of Reconfigurable Data Center Architectures
    Klaus-Tycho Foerster, Manya Ghobadi, and Stefan Schmid.
    14th ACM/IEEE Symposium on Architectures for Networking and Communications Systems (ANCS), Ithaca, NY, USA, July 2018.
    Documents: paper pdf link external

  11. Scheduling Congestion-Free Updates of Multiple Flows with Chronicle in Timed SDNs
    Jiaqi Zheng, Bo Li, Chen Tian, Klaus-Tycho Foerster, Stefan Schmid, Guihai Chen, and Jie Wu.
    38th IEEE International Conference on Distributed Computing Systems (ICDCS), Vienna, Austria, July 2018.
    Documents: paper pdf link external

  12. Waypoint Routing in Special Networks
    Saeed Akhoondian Amiri, Klaus-Tycho Foerster, Riko Jacob, Mahmoud Parham, and Stefan Schmid.
    17th IFIP Networking Conference (IFIP Networking), Zurich, Switzerland, May 2018.
    Documents: paper pdf

  13. Walking through Waypoints
    Saeed Akhoondian Amiri, Klaus-Tycho Foerster, and Stefan Schmid.
    13th Latin American Theoretical Informatics Symposium (LATIN), Buenos Aires, Argentina, April 2018.
    Documents: paper pdf link external

  14. Teaching Programming Skills in Primary School Mathematics Classes: An Evaluation using Game Programming
    Emmy-Charlotte Foerster, Klaus-Tycho Foerster, and Thomas Loewe.
    9th IEEE Global Engineering Education Conference (EDUCON), Santa Cruz de Tenerife, Canary Islands, Spain, April 2018.
    Documents: paper pdf link external

  15. TI-MFA: Keep Calm and Reroute Segments Fast
    Klaus-Tycho Foerster, Mahmoud Parham, Marco Chiesa, and Stefan Schmid
    21st IEEE Global Internet Symposium (GI), Honolulu, Hawaii, USA, April 2018.
    Documents: paper pdf link external

  16. Run, Walk, Crawl: Towards Dynamic Link Capacities
    Rachee Singh, Monia /Manya/ Ghobadi , Klaus-Tycho Foerster, Mark Filer, and Phillipa Gill
    16th ACM Workshop on Hot Topics in Networks (HotNets), Palo Alto, CA, USA, November 2017.
    Documents: paper pdf link external please also see: HotNets Dialogue

  17. On the Consistent Migration of Unsplittable Flows: Upper and Lower Complexity Bounds
    Klaus-Tycho Foerster.
    16th IEEE International Symposium on Network Computing and Applications (NCA), Cambridge, MA, USA, November 2017.
    Thanks for the travel grant by the Otto Mønsteds fond.
    Documents: paper pdf link external

  18. A Walk in the Clouds: Routing through VNFs on Bidirected Networks
    Klaus-Tycho Foerster, Mahmoud Parham and Stefan Schmid.
    3rd International Workshop on Algorithmic Aspects of Cloud Computing (ALGOCLOUD), Vienna, Austria, September 2017.
    Documents: paper pdf link external

  19. Understanding and Mitigating Packet Corruption in Data Center Networks
    Danyang Zhuo, Monia /Manya/ Ghobadi, Ratul Mahajan, Klaus-Tycho Foerster, Arvind Krishnamurthy, and Thomas Anderson.
    Annual Conference of the ACM Special Interest Group on Data Communication (SIGCOMM), Los Angeles, CA, USA, August 2017.
    Documents: paper pdf link external YouTube

  20. Wireless Evacuation on m Rays with k Searchers
    Sebastian Brandt, Klaus-Tycho Foerster, Benjamin Richner, and Roger Wattenhofer.
    24th International Colloquium on Structural Information and Communication Complexity (SIROCCO), Porquerolles, France, June 2017.
    Documents: paper pdf link external

  21. Multi-Agent Pathfinding with n Agents on Graphs with n Vertices: Combinatorial Classification and Tight Algorithmic Bounds
    Klaus-Tycho Foerster, Linus Groner, Torsten Hoefler, Michael Koenig, Sascha Schmid, and Roger Wattenhofer.
    10th International Conference on Algorithms and Complexity (CIAC), Athens, Greece, May 2017.
    Documents: paper pdf link external

  22. Teaching Spatial Geometry in a Virtual World: Using Minecraft in Mathematics in Grade 5/6
    Klaus-Tycho Foerster.
    8th IEEE Global Engineering Education Conference (EDUCON), Athens, Greece, April 2017.
    Documents: paper pdf link external

  23. Local Checkability in Dynamic Networks
    Klaus-Tycho Foerster, Oliver Richter, Jochen Seidel, and Roger Wattenhofer.
    18th International Conference on Distributed Computing and Networking (ICDCN), Hyderabad, India, January 2017.
    Documents: paper pdf link external

  24. Distributed Discussion Diarisation
    Pascal Bissig, Klaus-Tycho Foerster, Simon Tanner, and Roger Wattenhofer.
    14th Annual IEEE Consumer and Networking Conference (CCNC), Las Vegas, NV, USA, January 2017.
    Documents: paper pdf link external

  25. RTDS: Real-Time Discussion Statistics
    Pascal Bissig, Jan Deriu, Klaus-Tycho Foerster, and Roger Wattenhofer.
    15th International Conference on Mobile and Ubiquitous Multimedia (MUM), Rovaniemi, Finland, December 2016.
    Documents: paper pdf link external

  26. Reducing the Latency-Tail of Short-Lived Flows: Adding Forward Error Correction in Data Centers
    Klaus-Tycho Foerster, Demian Jaeger, David Stolz, and Roger Wattenhofer.
    15th IEEE International Symposium on Network Computing and Applications (NCA), Cambridge, MA, USA, November 2016.
    Documents: paper pdf link external

  27. Integrating Programming into the Mathematics Curriculum: Combining Scratch and Geometry in Grades 6 and 7
    Klaus-Tycho Foerster
    17th Annual Conference on Information Technology Education (SIGITE), Boston, MA, USA, September 2016.
    Documents: paper pdf link external

  28. The Power of Two in Consistent Network Updates: Hard Loop Freedom, Easy Flow Migration
    Klaus-Tycho Foerster and Roger Wattenhofer
    25th International Conference on Computer Communication and Networks (ICCCN), Waikoloa, Hi, USA, August 2016.
    Documents: paper pdf link external

  29. Consistent Updates in Software Defined Networks: On Dependencies, Loop Freedom, and Blackholes
    Klaus-Tycho Foerster, Ratul Mahajan, and Roger Wattenhofer.
    15th IFIP Networking Conference (IFIP Networking), Vienna, Austria, May 2016.
    Documents: paper pdf link external

  30. On Consistent Migration of Flows in SDNs (Best-in-session presentation award)
    Sebastian Brandt, Klaus-Tycho Foerster, and Roger Wattenhofer.
    36th IEEE International Conference on Computer Communications (INFOCOM), San Francisco, California, USA, April 2016.
    Documents: paper pdf link external

  31. Augmenting Anycast Network Flows (Best paper session)
    Sebastian Brandt, Klaus-Tycho Foerster, and Roger Wattenhofer.
    17th International Conference on Distributed Computing and Networking (ICDCN), Singapore, January 2016.
    Documents: paper pdf link external

  32. Local Checkability, No Strings Attached (Best paper award)
    Klaus-Tycho Foerster, Thomas Luedi, Jochen Seidel, and Roger Wattenhofer.
    17th International Conference on Distributed Computing and Networking (ICDCN), Singapore, January 2016.
    Documents: paper pdf link external

  33. Destroying networks for fun (and profit)
    Nick Shelly, Brendan Tschaen, Klaus-Tycho Foerster, Michael Chang, Theophilus Benson, and Laurent Vanbever.
    14th ACM Workshop on Hot Topics in Networks (HotNets), Philadelphia, PA, USA, November 2015.
    Documents: paper pdf link external

  34. Lower Bounds for the Capture Time: Linear, Quadratic, and Beyond
    Klaus-Tycho Foester, Rijad Nuridini, Jara Uitto, and Roger Wattenhofer.
    22nd International Colloquium on Structural Information and Communication Complexity (SIROCCO), Montserrat, Spain, July 2015.
    Documents: paper pdf link external

  35. SpareEye: A Smart Phone App that Enhances the Safety of the Inattentionally Blind
    Klaus-Tycho Foerster, Alex Gross, Nino Hail, Jara Uitto, and Roger Wattenhofer.
    The 13th International Conference on Mobile and Ubiquitous Multimedia (MUM), Melbourne, Australia, November 2014.
    Documents: paper pdf link external

  36. Deterministic Leader Election in Multi-Hop Beeping Networks
    Klaus-Tycho Foerster, Jochen Seidel, and Roger Wattenhofer.
    28th International Symposium on Distributed Computing (DISC), Austin, Texas, USA, October 2014.
    Documents: paper pdf link external

  37. Approximating Fault-Tolerant Domination in General Graphs
    Klaus-Tycho Foerster.
    10th Meeting on Analytic Algorithmics and Combinatorics (ANALCO) New Orleans, Louisiana, USA, January, 2013
    Documents: paper pdf link external

  38. Directed Graph Exploration
    Klaus-Tycho Foerster and Roger Wattenhofer.
    16th International Conference On Principles Of Distributed Systems (OPODIS), Rome, Italy, December 2012.
    Documents: paper pdf link external

Journals (peer-reviewed, national)

  1. Scratch im Geometrieunterricht
    Klaus-Tycho Foerster.
    mathematik lehren (ml), 32, No. 188, pp. 20-24, February 2015.
    Documents: abstract pdf link ME 2015d.00655 external

  2. (Netzwerk-)Spiele
    Klaus-Tycho Foerster.
    Computer+Unterricht (C+U), 9, No. 36, p. 24, November 1999.
    Documents: link ME 2000d.03004 external

  3. Warum gibt es an Ihrer Schule noch keine Computerspiele-AG? Plädoyer für die Einrichtung von Netzwerk-Computerspiele-AGs an Schulen
    Klaus-Tycho Foerster.
    Computer+Unterricht (C+U), 9, No. 36, pp. 22-23, November 1999.
    Documents: link ME 2001b.00181 external

Conference Proceedings (peer-reviewed, national)

  1. Vom Flaggenalphabet zur Vorratsdatenspeicherung: Schülerinnen und Schüler als Multiplikatoren technischer Aspekte der digitalen Welt
    Klaus-Tycho Foerster.
    17. GI-Fachtagung Informatik und Schule (INFOS) 2017. Oldenburg, Germany, September 2017.
    Documents: paper pdf

Contributed Articles (national)

  1. Scratch von Anfang an
    Klaus-Tycho Foerster.
    Beiträge zum Mathematikunterricht (BzMU) 2014. WTM-Verlag, Münster, pp. 373 - 376.
    Documents: paper pdf link external

  2. Die Programmiersprache Scratch in der Sekundarstufe I
    Klaus-Tycho Foerster.
    Beiträge zum Mathematikunterricht (BzMU) 2013. WTM-Verlag, Münster, pp. 316 - 319.
    Documents: paper pdf link external

  3. Raumgeometrie mit Minecraft: Raumvorstellung und kreative Kooperation zu Beginn der Sekundarstufe I
    Klaus-Tycho Foerster.
    Beiträge zum Mathematikunterricht (BzMU) 2012. WTM-Verlag, Münster, pp. 273-276.
    Documents: paper pdf link external

  4. Neue Möglichkeiten durch die Programmiersprache Scratch: Algorithmen und Programmierung für alle Fächer
    Klaus-Tycho Foerster.
    Beiträge zum Mathematikunterricht (BzMU) 2011. WTM-Verlag, Münster, pp. 262-266.
    Documents: paper pdf link external

Posters (peer-reviewed, international)

  1. A Concept for an Introduction to Parallelization in Java: Multithreading with Programmable Robots in Minecraft
    Klaus-Tycho Foerster, Michael Koenig, and Roger Wattenhofer.
    17th Annual Conference on Information Technology Education (SIGITE), Boston, MA, USA, September 2016.
    Documents: paper pdf link external

  2. Programming in Scratch and Mathematics: Augmenting Your Geometry Curriculum, Today!
    Klaus-Tycho Foerster.
    16th Annual Conference on Information Technology Education (SIGITE), Chicago, IL, USA, October 2015.
    Documents: paper pdf link external

Posters (peer-reviewed, international, without proceedings)

  1. Programming as an Everyday Tool in Mathematical Education
    Klaus-Tycho Foerster.
    13th International Congress on Mathematical Education (ICME), Hamburg, Germany, July 2016.
    Documents: conference ICME13 link TSG 42 (conftool) poster pdf

Dissertation

  1. Don't disturb my Flows: Algorithms for Consistent Network Updates in Software Defined Networks
    (Advisor: Roger Wattenhofer, Referees: Ratul Mahajan, Microsoft Research, and Stefan Schmid, Aalborg University)
    Diss ETH No. 23703, TIK-Schriftenreihe Nr. 166
    ISBN 978-1537297170, 2016

Chapters

  1. Chapter: Cryptography Basics
    Klaus-Tycho Foerster and Roger Wattenhofer.
    In: Roger Wattenhofer (Ed.), Distributed Ledger Technology: The Science of the Blockchain (pp. 49-70)
    ISBN 978-1544232102, 2017. Available on Amazon.

  2. Chapter: Quorum Systems
    Klaus-Tycho Foerster and Roger Wattenhofer.
    In: Roger Wattenhofer (Ed.), Distributed Ledger Technology: The Science of the Blockchain (pp. 87-104)
    ISBN 978-1544232102, 2017. Available on Amazon.

In the Press

Talks

Some talks:

Tech Reports

Note that the following documents are sometimes drafts only or work in progress.

  1. Online Graph Exploration on a Restricted Graph Class: Optimal Solutions for Tadpole Graphs
    Sebastian Brandt, Klaus-Tycho Foerster, Jonathan Maurer, and Roger Wattenhofer.
    ArXiv Technical Report, March 2019.
    Documents: paper pdf link external

  2. On the Power of Preprocessing in Decentralized Network Optimization
    Klaus-Tycho Foerster, Juho Hirvonen, Stefan Schmid, and Jukka Suomela.
    ArXiv Technical Report, December 2018.
    Documents: paper pdf link external

  3. Walking Through Waypoints
    Saeed Akhoondian Amiri, Klaus-Tycho Foerster, and Stefan Schmid.
    ArXiv Technical Report, August 2017, last revised April 2018.
    Documents: paper pdf link external

  4. Charting the Complexity Landscape of Waypoint Routing
    Saeed Akhoondian Amiri, Klaus-Tycho Foerster, Riko Jacob, and Stefan Schmid.
    ArXiv Technical Report, April 2017, last revised September 2017.
    Documents: paper pdf link external

  5. Survey of Consistent Software-Defined Network Updates
    Klaus-Tycho Foerster, Stefan Schmid, and Stefano Vissicchio.
    ArXiv Technical Report, September 2016, revised February 2018, accepted version from October 2018.
    Documents: paper pdf link external

  6. The Solitaire Memory Game
    Klaus-Tycho Foerster and Roger Wattenhofer.
    Technical Report, ETH Zurich, 2013.
    Documents: paper pdf
    Please see the following paper by Velleman and Warrington where the conjectured number of roughly 1.61n moves was proven: What to Expect in a Game of Memory.

Teaching

Teaching Assistant:

Laboratory and practical classes:

Courses:

Teacher:

Students

Community

TPCs

Editorial Board

Working Groups

TPCs (special sessions)

Miscellany

Reviewer (Conferences):

Reviewer (Journals):

I also serve as reviewer for the Mathematical Reviews (MR) of the American Mathematical Society (AMS).

I moreover served as an expert reviewer for the German-Israeli Foundation for Scientific Research and Development (GIF).

Projects

I am grateful to have been funded by the following projects: I am grateful to have received the following additional funding:

Extended CV

As of 2018, Klaus-Tycho Foerster is a postdoctoral researcher at the University of Vienna, Austria, working with Stefan Schmid. In 2017 he was a postdoc at Aalborg University, Denmark. He was a visiting researcher at Microsoft Research, Redmond, USA, working with Ratul Mahajan for Fall 2016. His doctoral studies took place from 2011 to 2016 in the Distributed Computing Group at ETH Zurich, Switzerland, under the supervision of Roger Wattenhofer. He received his PhD degree from ETH Zurich in September 2016.
Prior to joining ETH as a research assistant, he earned his Diplomas in mathematics (advised by Sándor Fekete, 2007, pre-diploma 2005) and computer science (advised by Jirí Adámek, 2011, pre-diploma 2005), both at the Braunschweig University of Technology, Germany. In parallel, he worked for 11 months as a research assistant at the University of Hildesheim, Germany, with Barbara Schmidt-Thieme, and obtained his second state examination (advised by Eckart Modrow, 2010), teaching mathematics and computer science for two years at the Max-Planck Gymnasium Göttingen, Germany.



I would like to thank Stefan Schmid for allowing me to copy the layout of his website. Last Change: Thursday, 18-April-2019